EXHIBIT 4.2


                     INVESTOR REGISTRATION RIGHTS AGREEMENT

     THIS REGISTRATION RIGHTS AGREEMENT (this "Agreement"),  dated as of May 27,
2005, by and among AVITAR, INC., a Delaware  corporation,  (the "Company"),  and
the  undersigned   investors   (each,  an  "Investor"  and   collectively,   the
"Investors").

     WHEREAS:

     A. In connection  with the Securities  Purchase  Agreement by and among the
parties hereto of even date herewith (the "Securities Purchase Agreement"),  the
Company  has  agreed,  upon the  terms  and  subject  to the  conditions  of the
Securities  Purchase  Agreement,  to issue  and sell to the  Investors  Series E
Convertible  Preferred  Stock (the  "Series E Preferred  Stock")  which shall be
convertible  into that number of shares of the Company's common stock, par value
$0.01 per share (the "Common  Stock"),  pursuant to the terms of the  Securities
Purchase   Agreement  for  an  aggregate  purchase  price  of  up  to  $750,000.
Capitalized  terms not defined herein shall have the meaning ascribed to them in
the Securities Purchase Agreement.

     B. To induce the Investors to execute and deliver the  Securities  Purchase
Agreement,  the Company has agreed to provide certain  registration rights under
the  Securities  Act of 1933, as amended,  and the rules and  regulations  there
under, or any similar  successor  statute  (collectively,  the "1933 Act"),  and
applicable state securities laws.

     NOW,  THEREFORE,  in consideration of the premises and the mutual covenants
contained  herein and other good and  valuable  consideration,  the  receipt and
sufficiency  of which are hereby  acknowledged,  the Company  and the  Investors
hereby agree as follows:

1. DEFINITIONS.

     As used in this  Agreement,  the  following  terms shall have the following
meanings:

(a) "Investor"  means an Investor and any transferee or assignee thereof to whom
an Investor  assigns its rights  under this  Agreement  and who agrees to become
bound by the provisions of this Agreement in accordance with Section 9 hereof.

(b) "Person" means a corporation, a limited liability company, an association, a
partnership,  an  organization,  a business,  an individual,  a governmental  or
political subdivision thereof or a governmental agency.

(c)  "Register,"  "registered,"  and  "registration"  refer  to  a  registration
effected by preparing and filing one or more Registration Statements (as defined
below) in  compliance  with the 1933 Act and pursuant to Rule 415 under the 1933
Act or any successor rule  providing for offering  securities on a continuous or
delayed basis ("Rule 415"),  and the declaration or ordering of effectiveness of
such Registration  Statement(s) by the United States Securities and Exchange SEC
(the "SEC").

(d)  "Registrable  Securities"  means the  shares of Common  Stock  issuable  to
Investors  upon  conversion  of the Series E  Preferred  Stock  pursuant  to the
Securities Purchase Agreement.

(e) "Registration  Statement" means a registration  statement under the 1933 Act
which covers the Registrable Securities.

2. REGISTRATION.

(a) Subject to the terms and  conditions  of this  Agreement,  the Company shall
prepare and file,  no later than  thirty  (30) days from the date First  Closing
pursuant  to the  Securities  Purchase  Agreement  of even  date  herewith  (the
"Scheduled Filing Deadline"),  with the SEC a registration statement on Form S-1
or SB-2 (or,  if the Company is then  eligible,  on Form S-3) under the 1933 Act
(the "Initial  Registration  Statement") for the  registration for the resale by
all Investors who purchased  Series E Preferred Stock pursuant to the Securities
Purchase  Agreement  15,000,000  shares  of  Common  Stock  to  be  issued  upon
conversion  of the Series E Preferred  Stock issued  pursuant to the  Securities
Purchase Agreement. The Company shall cause the Registration Statement to remain
effective until all of the Registrable  Securities have been sold.  Prior to the
filing of the  Registration  Statement with the SEC, the Company shall furnish a
copy of the Initial  Registration  Statement to the Investors for its review and
comment.

(b) Effectiveness of the Initial Registration  Statement.  The Company shall use
its  best  efforts  (i) to have  the  Initial  Registration  Statement  declared
effective  by the SEC no later than  ninety (90) days after the date hereof (the
"Scheduled Effective Deadline") and (ii) to insure that the Initial Registration
Statement and any subsequent  Registration Statement remains in effect until all
of  the  Registrable  Securities  have  been  sold,  subject  to the  terms  and
conditions of this Agreement.  It shall be an event of default  hereunder if the
Initial Registration  Statement is not filed by the Scheduled Filing Deadline or
not declared effective by the SEC by the Scheduled Effective Deadline.

(c) Failure to File or Obtain  Effectiveness of the Registration  Statement.  In
the event  the  Registration  Statement  is not  filed by the  Scheduled  Filing
Deadline  or is not  declared  effective  by the SEC on or before the  Scheduled
Effective  Date,  or if after  the  Registration  Statement  has  been  declared
effective  by the  SEC,  sales  cannot  be  made  pursuant  to the  Registration
Statement  (whether  because  of a failure  to keep the  Registration  Statement
effective,  failure to disclose such information as is necessary for sales to be
made  pursuant to the  Registration  Statement,  failure to register  sufficient
shares of Common  Stock or otherwise  then as partial  relief for the damages to
any holder of Registrable Securities by reason of any such delay in or reduction
of its ability to sell the underlying shares of Common Stock (which remedy shall
not be  exclusive of any other  remedies at law or in equity),  the Company will
pay as liquidated damages (the "Liquidated Damages") to the holder a cash amount
within three (3) business  days,  after demand  therefore,  equal to two percent
(2%) of the  liquidated  value of the Series E Preferred  Stock  outstanding  as
Liquidated  Damages for each thirty (30) day period after the  Scheduled  Filing
Deadline or the  Scheduled  Effective  Date as the case may be. In the event the
Company  fails to obtain an  effective  registration  statement by the 360th day
following  the First  Closing,  the Company  shall redeem the Series E Preferred
Stock as set forth in Section 6.2 of the Certificate of Designations;  provided,
however, that this provision shall not limit the Investor's right to enforce any
other  provision  of this  Agreement or any other  contract  entered into by the
Company and Investor on the date hereof.

(d) Liquidated  Damages.  The Company and the Investor  hereto  acknowledge  and
agree  that the sums  payable  under  subsection  2(c)  above  shall  constitute
liquidated damages and not penalties.  The parties further  acknowledge that (i)
the amount of loss or damages likely to be incurred is incapable or is difficult
to precisely  estimate,  (ii) the amounts  specified in such  subsections bear a
reasonable  relationship to, and are not plainly or grossly  disproportionate to
the probable  loss likely to be incurred in  connection  with any failure by the
Company to obtain or maintain the  effectiveness  of a  Registration  Statement,
(iii) one of the reasons for the Company and the Investor  reaching an agreement
as to such amounts was the  uncertainty  and cost of  litigation  regarding  the
question  of  actual  damages,  and  (iv)  the  Company  and  the  Investor  are
sophisticated  business parties and have been  represented by sophisticated  and
able legal counsel and negotiated this Agreement at arm's length.

3. RELATED OBLIGATIONS.

(a) The Company shall keep the Registration Statement effective pursuant to Rule
415 at all times  until the date on which the  Investor  shall have sold all the
Registrable Securities covered by such Registration Statement (the "Registration
Period"),  which Registration Statement (including any amendments or supplements
thereto  and  prospectuses  contained  therein)  shall not  contain  any  untrue
statement  of a material  fact or omit to state a material  fact  required to be
stated  therein,  or necessary to make the statements  therein,  in light of the
circumstances in which they were made, not misleading.

(b) The Company shall prepare and file with the SEC such  amendments  (including
post-effective  amendments) and supplements to a Registration  Statement and the
prospectus used in connection with such Registration Statement, which prospectus
is to be filed  pursuant to Rule 424  promulgated  under the 1933 Act, as may be
necessary to keep such Registration  Statement effective at all times during the
Registration Period, and, during such period,  comply with the provisions of the
1933 Act with respect to the  disposition of all  Registrable  Securities of the
Company  covered by such  Registration  Statement until such time as all of such
Registrable  Securities  shall  have been  disposed  of in  accordance  with the
intended methods of disposition by the seller or sellers thereof as set forth in
such  Registration  Statement.  In the case of amendments  and  supplements to a
Registration Statement which are required to be filed pursuant to this Agreement
(including  pursuant to this Section 3(b)) by reason of the  Company's  filing a
report on Form 10-KSB, Form 10-QSB or Form 8-K or any analogous report under the
Securities  Exchange Act of 1934, as amended (the "1934 Act"), the Company shall
incorporate  such  report  by  reference  into the  Registration  Statement,  if
applicable,  or shall file such  amendments or  supplements  with the SEC on the
same day on which the 1934 Act report is filed which created the requirement for
the Company to amend or supplement the Registration Statement.

(c) The Company shall furnish to each Investor whose Registrable  Securities are
included in any  Registration  Statement,  without charge,  (i) at least one (1)
copy of such  Registration  Statement  as declared  effective by the SEC and any
amendment(s)  thereto,   including  financial  statements  and  schedules,   all
documents  incorporated therein by reference,  all exhibits and each preliminary
prospectus,  (ii) ten (10)  copies  of the  final  prospectus  included  in such
Registration Statement and all amendments and supplements thereto (or such other
number of copies as such Investor may  reasonably  request) and (iii) such other
documents as such Investor may reasonably  request from time to time in order to
facilitate the disposition of the Registrable Securities owned by such Investor.

(d) The  Company  shall use its best  efforts to (i)  register  and  qualify the
Registrable  Securities  covered by a  Registration  Statement  under such other
securities or "blue sky" laws of such  jurisdictions in the United States as any
Investor reasonably requests, (ii) prepare and file in those jurisdictions, such
amendments  (including  post-effective   amendments)  and  supplements  to  such
registrations   and   qualifications   as  may  be  necessary  to  maintain  the
effectiveness  thereof  during the  Registration  Period,  (iii) take such other
actions as may be necessary to maintain such registrations and qualifications in
effect at all times  during  the  Registration  Period,  and (iv) take all other
actions reasonably necessary or advisable to qualify the Registrable  Securities
for sale in such jurisdictions; provided, however, that the Company shall not be
required  in  connection  therewith  or as a  condition  thereto to (w) make any
change to its  certificate  of  incorporation  or  by-laws,  (x)  qualify  to do
business in any jurisdiction where it would not otherwise be required to qualify
but for this Section 3(d),  (y) subject  itself to general  taxation in any such
jurisdiction,  or (z) file a general  consent  to service of process in any such
jurisdiction.  The  Company  shall  promptly  notify  each  Investor  who  holds
Registrable  Securities of the receipt by the Company of any  notification  with
respect to the suspension of the  registration  or  qualification  of any of the
Registrable  Securities  for sale under the securities or "blue sky" laws of any
jurisdiction  in the  United  States  or its  receipt  of  actual  notice of the
initiation or threat of any proceeding for such purpose.

(e)  As  promptly  as  practicable   after  becoming  aware  of  such  event  or
development,  the Company shall notify each Investor in writing of the happening
of any event as a result  of which the  prospectus  included  in a  Registration
Statement, as then in effect, includes an untrue statement of a material fact or
omission to state a material fact required to be stated  therein or necessary to
make the statements therein, in light of the circumstances under which they were
made,  not  misleading  (provided that in no event shall such notice contain any
material, nonpublic information), and promptly prepare a supplement or amendment
to such Registration Statement to correct such untrue statement or omission, and
deliver ten (10) copies of such  supplement or amendment to each  Investor.  The
Company  shall  also  promptly  notify  each  Investor  in  writing  (i)  when a
prospectus or any  prospectus  supplement or  post-effective  amendment has been
filed,  and when a Registration  Statement or any  post-effective  amendment has
become effective  (notification of such effectiveness shall be delivered to each
Investor  by  facsimile  on the  same  day of such  effectiveness),  (ii) of any
request by the SEC for amendments or supplements to a Registration  Statement or
related prospectus or related information, and (iii) of the Company's reasonable
determination that a post-effective  amendment to a Registration Statement would
be appropriate.

(f) The Company  shall use its best  efforts to prevent the issuance of any stop
order or other suspension of effectiveness of a Registration  Statement,  or the
suspension of the qualification of any of the Registrable Securities for sale in
any  jurisdiction  within the United  States of America and, if such an order or
suspension  is issued,  to obtain the  withdrawal of such order or suspension at
the earliest  possible moment and to notify each Investor who holds  Registrable
Securities  being sold of the issuance of such order and the resolution  thereof
or its receipt of actual notice of the  initiation  or threat of any  proceeding
for such purpose.

(g) [OMITTED]

(h) The Company shall make available for inspection by (i) any Investor and (ii)
one  (1)  firm  of  accountants  or  other  agents  retained  by  the  Investors
(collectively,  the "Inspectors") all pertinent financial and other records, and
pertinent corporate documents and properties of the Company  (collectively,  the
"Records"), as shall be reasonably deemed necessary by each Inspector, and cause
the Company's officers,  directors and employees to supply all information which
any Inspector may reasonably  request;  provided,  however,  that each Inspector
shall agree, and each Investor hereby agrees,  to hold in strict  confidence and
shall not make any disclosure (except to an Investor) or use any Record or other
information which the Company  determines in good faith to be confidential,  and
of which determination the Inspectors are so notified, unless (a) the disclosure
of such Records is necessary to avoid or correct a  misstatement  or omission in
any Registration  Statement or is otherwise required under the 1933 Act, (b) the
release of such Records is ordered pursuant to a final,  non-appealable subpoena
or order from a court or government body of competent  jurisdiction,  or (c) the
information  in such  Records has been made  generally  available  to the public
other than by  disclosure  in violation of this or any other  agreement of which
the  Inspector  and the Investor has  knowledge.  Each  Investor  agrees that it
shall,  upon learning that disclosure of such Records is sought in or by a court
or  governmental  body of competent  jurisdiction  or through other means,  give
prompt notice to the Company and allow the Company, at its expense, to undertake
appropriate  action to prevent  disclosure  of, or to obtain a protective  order
for, the Records deemed confidential.

(i) The  Company  shall  hold in  confidence  and not  make  any  disclosure  of
information concerning an Investor provided to the Company unless (i) disclosure
of such  information  is necessary  to comply with  federal or state  securities
laws, (ii) the disclosure of such information is necessary to avoid or correct a
misstatement  or omission in any  Registration  Statement,  (iii) the release of
such   information   is  ordered   pursuant  to  a  subpoena  or  other   final,
non-appealable   order  from  a  court  or   governmental   body  of   competent
jurisdiction,  or (iv) such information has been made generally available to the
public other than by  disclosure  in  violation  of this  Agreement or any other
agreement.  The Company agrees that it shall,  upon learning that  disclosure of
such  information  concerning  an  Investor  is  sought  in  or  by a  court  or
governmental body of competent  jurisdiction or through other means, give prompt
written  notice to such  Investor  and allow such  Investor,  at the  Investor's
expense, to undertake  appropriate action to prevent disclosure of, or to obtain
a protective order for, such information.

(j) The Company shall use its best efforts  either to cause all the  Registrable
Securities  covered  by a  Registration  Statement  (i)  to be  listed  on  each
securities  exchange on which  securities  of the same class or series issued by
the  Company  are  then  listed,  if any,  if the  listing  of such  Registrable
Securities  is then  permitted  under  the  rules of such  exchange  or (ii) the
inclusion for quotation on the National Association of Securities Dealers,  Inc.
OTC Bulletin Board for such  Registrable  Securities.  The Company shall pay all
fees and  expenses in  connection  with  satisfying  its  obligation  under this
Section 3(j).

(k) The  Company  shall  cooperate  with  the  Investors  who  hold  Registrable
Securities being offered and, to the extent applicable, to facilitate the timely
preparation  and delivery of certificates  (not bearing any restrictive  legend)
representing the Registrable Securities to be offered pursuant to a Registration
Statement and enable such  certificates to be in such  denominations or amounts,
as the case may be, as the Investors may  reasonably  request and  registered in
such names as the Investors may request.

(l) The Company shall use its best efforts to cause the  Registrable  Securities
covered  by the  applicable  Registration  Statement  to be  registered  with or
approved by such other governmental  agencies or authorities as may be necessary
to consummate the disposition of such Registrable Securities.

(m) The Company shall make generally  available to its security  holders as soon
as practical,  but not later than ninety (90) days after the close of the period
covered thereby, an earnings statement (in form complying with the provisions of
Rule 158 under the 1933 Act)  covering a twelve (12) month period  beginning not
later than the first day of the  Company's  fiscal  quarter next  following  the
effective date of the Registration Statement.

(n) The  Company  shall  otherwise  use its  best  efforts  to  comply  with all
applicable  rules and regulations of the SEC in connection with any registration
hereunder.

(o) Within two (2) business  days after a  Registration  Statement  which covers
Registrable  Securities  is declared  effective  by the SEC,  the Company  shall
deliver,  and shall  cause legal  counsel  for the  Company to  deliver,  to the
transfer  agent for such  Registrable  Securities  (with copies to the Investors
whose  Registrable  Securities  are  included  in such  Registration  Statement)
confirmation that such Registration Statement has been declared effective by the
SEC in the form attached hereto as Exhibit A.

(p) The Company shall take all other  reasonable  actions  necessary to expedite
and facilitate  disposition by the Investors of Registrable  Securities pursuant
to a Registration Statement.

4. OBLIGATIONS OF THE INVESTORS.

     Each Investor  agrees that,  upon receipt of any notice from the Company of
the  happening  of any event of the kind  described in Section 3(f) or the first
sentence of 3(e),  such Investor will  immediately  discontinue  disposition  of
Registrable  Securities pursuant to any Registration  Statement(s) covering such
Registrable  Securities  until  such  Investor's  receipt  of the  copies of the
supplemented  or amended  prospectus  contemplated by Section 3(e) or receipt of
notice that no supplement or amendment is required.  Notwithstanding anything to
the contrary,  the Company shall cause its transfer agent to deliver  unlegended
certificates  for  shares of Common  Stock to a  transferee  of an  Investor  in
accordance  with the terms of the  Securities  Purchase  Agreement in connection
with any sale of  Registrable  Securities  with respect to which an Investor has
entered  into a contract  for sale prior to the  Investor's  receipt of a notice
from the Company of the happening of any event of the kind  described in Section
3(f) or the  first  sentence  of 3(e) and for  which  the  Investor  has not yet
settled.

5. EXPENSES OF REGISTRATION.

     All  expenses  incurred  in  connection  with  registrations,   filings  or
qualifications pursuant to Sections 2 and 3, including,  without limitation, all
registration,  listing and qualifications fees,  printers,  legal and accounting
fees shall be paid by the Company.

6.       INDEMNIFICATION.

     With respect to Registrable Securities which are included in a Registration
Statement under this Agreement:

(a) To the fullest  extent  permitted by law, the Company will, and hereby does,
indemnify,  hold harmless and defend each  Investor,  the  directors,  officers,
partners,  employees,  agents,  representatives of, and each Person, if any, who
controls any Investor  within the meaning of the 1933 Act or the 1934 Act (each,
an "Indemnified  Person"),  against any losses,  claims,  damages,  liabilities,
judgments, fines, penalties, charges, costs, reasonable attorneys' fees, amounts
paid in  settlement  or  expenses,  joint or  several  (collectively,  "Claims")
incurred in  investigating,  preparing or  defending  any action,  claim,  suit,
inquiry,  proceeding,  investigation  or appeal  taken from the  foregoing by or
before any court or governmental,  administrative  or other  regulatory  agency,
body or the SEC,  whether  pending or threatened,  whether or not an indemnified
party is or may be a party thereto ("Indemnified Damages"), to which any of them
may become subject  insofar as such Claims (or actions or  proceedings,  whether
commenced or threatened, in respect thereof) arise out of or are based upon: (i)
any  untrue  statement  or alleged  untrue  statement  of a  material  fact in a
Registration Statement or any post-effective  amendment thereto or in any filing
made in connection with the  qualification  of the offering under the securities
or other "blue sky" laws of any jurisdiction in which Registrable Securities are
offered  ("Blue Sky  Filing"),  or the  omission or alleged  omission to state a
material fact required to be stated  therein or necessary to make the statements
therein not misleading; (ii) any untrue statement or alleged untrue statement of
a material fact contained in any final  prospectus (as amended or  supplemented,
if the Company files any amendment  thereof or supplement  thereto with the SEC)
or the omission or alleged omission to state therein any material fact necessary
to make the statements made therein,  in light of the circumstances  under which
the  statements  therein were made,  not  misleading;  or (iii) any violation or
alleged  violation  by the Company of the 1933 Act, the 1934 Act, any other law,
including,  without  limitation,  any  state  securities  law,  or any  rule  or
regulation  there  under  relating  to the  offer  or  sale  of the  Registrable
Securities  pursuant to a  Registration  Statement (the matters in the foregoing
clauses (i) through (iii) being, collectively,  "Violations"). The Company shall
reimburse  the  Investors  and each such  controlling  person  promptly  as such
expenses  are  incurred  and  are  due  and  payable,  for  any  legal  fees  or
disbursements or other reasonable  expenses  incurred by them in connection with
investigating  or  defending  any such  Claim.  Notwithstanding  anything to the
contrary  contained  herein,  the  indemnification  agreement  contained in this
Section 6(a):  (x) shall not apply to a Claim by an  Indemnified  Person arising
out of or based upon a Violation which occurs in reliance upon and in conformity
with information  furnished in writing to the Company by such Indemnified Person
expressly  for  use in  connection  with  the  preparation  of the  Registration
Statement or any such amendment thereof or supplement thereto;  (y) shall not be
available  to the extent  such Claim is based on a failure  of the  Investor  to
deliver  or to  cause to be  delivered  the  prospectus  made  available  by the
Company, if such prospectus was timely made available by the Company pursuant to
Section 3(c); and (z) shall not apply to amounts paid in settlement of any Claim
if such settlement is effected without the prior written consent of the Company,
which consent shall not be unreasonably withheld. Such indemnity shall remain in
full force and effect  regardless of any  investigation  made by or on behalf of
the  Indemnified  Person  and shall  survive  the  transfer  of the  Registrable
Securities by the Investors pursuant to Section 9 hereof.

(b) In  connection  with a  Registration  Statement,  each  Investor  agrees  to
severally  and not jointly  indemnify,  hold  harmless  and defend,  to the same
extent and in the same manner as is set forth in Section 6(a), the Company, each
of its directors, each of its officers,  employees,  representatives,  or agents
and each Person, if any, who controls the Company within the meaning of the 1933
Act or the  1934  Act  (each  an  "Indemnified  Party"),  against  any  Claim or
Indemnified Damages to which any of them may become subject, under the 1933 Act,
the 1934 Act or otherwise,  insofar as such Claim or  Indemnified  Damages arise
out of or is based upon any Violation,  in each case to the extent,  and only to
the extent,  that such Violation  occurs in reliance upon and in conformity with
written information  furnished to the Company by such Investor expressly for use
in connection with such  Registration  Statement;  and, subject to Section 6(d),
such Investor will reimburse any legal or other expenses  reasonably incurred by
them in connection  with  investigating  or defending any such Claim;  provided,
however,  that the  indemnity  agreement  contained in this Section 6(b) and the
agreement with respect to contribution contained in Section 7 shall not apply to
amounts paid in settlement of any Claim if such  settlement is effected  without
the  prior  written  consent  of  such  Investor,  which  consent  shall  not be
unreasonably withheld;  provided,  further,  however, that the Investor shall be
liable under this  Section  6(b) for only that amount of a Claim or  Indemnified
Damages as does not exceed the net proceeds to such  Investor as a result of the
sale of Registrable  Securities  pursuant to such Registration  Statement.  Such
indemnity shall remain in full force and effect  regardless of any investigation
made by or on behalf of such Indemnified Party and shall survive the transfer of
the   Registrable   Securities   by  the   Investors   pursuant  to  Section  9.
Notwithstanding  anything to the contrary contained herein, the  indemnification
agreement  contained in this Section 6(b) with respect to any  prospectus  shall
not inure to the benefit of any  Indemnified  Party if the untrue  statement  or
omission of material fact contained in the prospectus was corrected and such new
prospectus  was delivered to each Investor  prior to such  Investor's use of the
prospectus to which the Claim relates.

(c) Promptly after receipt by an Indemnified  Person or Indemnified  Party under
this  Section 6 of  notice  of the  commencement  of any  action  or  proceeding
(including  any  governmental  action or  proceeding)  involving  a Claim,  such
Indemnified  Person or Indemnified Party shall, if a Claim in respect thereof is
to be made against any  indemnifying  party under this Section 6, deliver to the
indemnifying  party  a  written  notice  of the  commencement  thereof,  and the
indemnifying  party shall have the right to  participate  in, and, to the extent
the indemnifying  party so desires,  jointly with any other  indemnifying  party
similarly  noticed,  to assume  control  of the  defense  thereof  with  counsel
mutually  satisfactory to the indemnifying  party and the Indemnified  Person or
the  Indemnified  Party,  as  the  case  may  be;  provided,  however,  that  an
Indemnified  Person or Indemnified  Party shall have the right to retain its own
counsel  with the fees and  expenses  of not more than one (1)  counsel for such
Indemnified  Person or Indemnified  Party to be paid by the indemnifying  party,
if, in the reasonable opinion of counsel retained by the indemnifying party, the
representation  by such counsel of the Indemnified  Person or Indemnified  Party
and the  indemnifying  party would be  inappropriate  due to actual or potential
differing interests between such Indemnified Person or Indemnified Party and any
other party  represented  by such counsel in such  proceeding.  The  Indemnified
Party or Indemnified Person shall cooperate fully with the indemnifying party in
connection  with any  negotiation  or defense of any such action or claim by the
indemnifying  party and shall furnish to the indemnifying  party all information
reasonably  available  to the  Indemnified  Party or  Indemnified  Person  which
relates  to such  action  or  claim.  The  indemnifying  party  shall  keep  the
Indemnified  Party or  Indemnified  Person fully apprised at all times as to the
status of the defense or any settlement  negotiations  with respect thereto.  No
indemnifying  party shall be liable for any  settlement of any action,  claim or
proceeding effected without its prior written consent;  provided,  however, that
the indemnifying party shall not unreasonably  withhold,  delay or condition its
consent.  No indemnifying party shall,  without the prior written consent of the
Indemnified  Party or  Indemnified  Person,  consent to entry of any judgment or
enter into any  settlement  or other  compromise  which  does not  include as an
unconditional  term  thereof  the giving by the  claimant or  plaintiff  to such
Indemnified  Party or  Indemnified  Person of a release  from all  liability  in
respect to such claim or litigation.  Following  indemnification as provided for
hereunder,  the  indemnifying  party  shall be  subrogated  to all rights of the
Indemnified Party or Indemnified Person with respect to all third parties, firms
or corporations  relating to the matter for which indemnification has been made.
The  failure  to  deliver  written  notice to the  indemnifying  party  within a
reasonable  time of the  commencement  of any such action shall not relieve such
indemnifying  party of any liability to the  Indemnified  Person or  Indemnified
Party under this Section 6, except to the extent that the indemnifying  party is
prejudiced in its ability to defend such action.

(d) The  indemnification  required  by this  Section 6 shall be made by periodic
payments  of the  amount  thereof  during  the  course of the  investigation  or
defense, as and when bills are received or Indemnified Damages are incurred.

(e) The indemnity  agreements  contained  herein shall be in addition to (i) any
cause of action or similar right of the Indemnified Party or Indemnified  Person
against  the  indemnifying  party  or  others,  and  (ii)  any  liabilities  the
indemnifying party may be subject to pursuant to the law.

7. CONTRIBUTION.

     To the extent any indemnification by an indemnifying party is prohibited or
limited by law, the indemnifying  party agrees to make the maximum  contribution
with respect to any amounts for which it would otherwise be liable under Section
6 to the fullest extent permitted by law; provided, however, that: (i) no seller
of Registrable  Securities  guilty of fraudulent  misrepresentation  (within the
meaning of Section 11(f) of the 1933 Act) shall be entitled to contribution from
any  seller  of  Registrable   Securities  who  was  not  guilty  of  fraudulent
misrepresentation; and (ii) contribution by any seller of Registrable Securities
shall be limited in amount to the net amount of proceeds received by such seller
from the sale of such Registrable Securities.

8. REPORTS UNDER THE 1934 ACT.

     With a view to making  available to the  Investors the benefits of Rule 144
promulgated under the 1933 Act or any similar rule or regulation of the SEC that
may at any time permit the  Investors to sell  securities  of the Company to the
public without registration ("Rule 144") the Company agrees to:

(a) make and keep public  information  available,  as those terms are understood
and defined in Rule 144;

(b)  file  with the SEC in a timely  manner  all  reports  and  other  documents
required  of the  Company  under  the  1933  Act and the 1934 Act so long as the
Company remains subject to such  requirements  (it being understood that nothing
herein  shall  limit  the  Company's  obligations  under  Section  4(c)  of  the
Securities  Purchase  Agreement)  and the  filing  of  such  reports  and  other
documents as are required by the applicable provisions of Rule 144; and

(c)  furnish  to  each  Investor  so  long as  such  Investor  owns  Registrable
Securities,  promptly upon request,  (i) a written statement by the Company that
it has complied  with the reporting  requirements  of Rule 144, the 1933 Act and
the 1934 Act, (ii) a copy of the most recent  annual or quarterly  report of the
Company and such other reports and documents so filed by the Company,  and (iii)
such other information as may be reasonably requested to permit the Investors to
sell such securities pursuant to Rule 144 without registration.

9. ASSIGNMENT OF REGISTRATION RIGHTS.

     The rights under this Agreement  shall be  automatically  assignable by the
Investors to any transferee of all or any portion of Registrable  Securities if:
(i) the  Investor  agrees in writing with the  transferee  or assignee to assign
such rights,  and a copy of such  agreement is furnished to the Company within a
reasonable time after such assignment;  (ii) the Company is, within a reasonable
time after such transfer or assignment, furnished with written notice of (a) the
name and address of such  transferee or assignee,  and (b) the  securities  with
respect to which such  registration  rights are being  transferred  or assigned;
(iii) at or before the time the Company receives the written notice contemplated
by clause (ii) of this  sentence the  transferee  or assignee  agrees in writing
with the Company to be bound by all of the provisions contained herein; and (iv)
such  transfer   shall  have  been  made  in  accordance   with  the  applicable
requirements of the Securities Agreement.

10. AMENDMENT OF REGISTRATION RIGHTS.

     Provisions of this Agreement may be amended and the observance  thereof may
be waived (either generally or in a particular instance and either retroactively
or  prospectively),  only with the written  consent of the Company and Investors
who then  hold at least  two-thirds  (2/3) of the  Registrable  Securities.  Any
amendment or waiver effected in accordance with this Section 10 shall be binding
upon each Investor and the Company.  No such amendment shall be effective to the
extent  that it  applies to fewer  than all of the  holders  of the  Registrable
Securities.  No consideration shall be offered or paid to any Person to amend or
consent to a waiver or  modification  of any provision of any of this  Agreement
unless the same  consideration  also is  offered  to all of the  parties to this
Agreement.

11. MISCELLANEOUS.

(a) A Person is deemed to be a holder of  Registrable  Securities  whenever such
Person owns or is deemed to own of record such  Registrable  Securities.  If the
Company receives conflicting instructions,  notices or elections from two (2) or
more Persons with respect to the same Registrable Securities,  the Company shall
act upon  the  basis of  instructions,  notice  or  election  received  from the
registered owner of such Registrable Securities.

(b) Any notices, consents, waivers or other communications required or permitted
to be given  under the terms of this  Agreement  must be in writing  and will be
deemed to have been delivered: (i) upon receipt, when delivered personally; (ii)
upon receipt,  when sent by facsimile (provided  confirmation of transmission is
mechanically or electronically generated and kept on file by the sending party);
or (iii)  one (1)  business  day  after  deposit  with a  nationally  recognized
overnight  delivery  service,  in each case  properly  addressed to the party to
receive the same.  The addresses and facsimile  numbers for such  communications
shall be:

If to the Company, to:  Avitar, Inc.
                        65 Dan Road
                        Canton, MA 02021
                        Attention:         Peter P. Phildius
                        Telephone:        (781) 821-2440
                        Facsimile:        (781) 821-4458

With a copy to:         Dolgenos Newman & Cronin LLP
                        96 Spring Street
                        New York, NY 10012
                        Attention:        Eugene M Cronin, Esq.
                        Telephone:        (212) 925-2800
                        Facsimile:        (212) 925-0690

If to an  Investor,  to its  address  and  facsimile  number on the  Schedule of
Investors attached hereto, with copies to such Investor's representatives as set
forth on the  Schedule of Investors or to such other  address  and/or  facsimile
number and/or to the  attention of such other person as the recipient  party has
specified by written notice given to each other party five (5) days prior to the
effectiveness of such change.  Written  confirmation of receipt (A) given by the
recipient  of  such  notice,  consent,   waiver  or  other  communication,   (B)
mechanically  or  electronically  generated  by the sender's  facsimile  machine
containing the time, date,  recipient facsimile number and an image of the first
page of such  transmission  or (C)  provided by a courier or  overnight  courier
service shall be rebuttable  evidence of personal service,  receipt by facsimile
or receipt from a nationally recognized overnight delivery service in accordance
with clause (i), (ii) or (iii) above, respectively.

(c) Failure of any party to exercise any right or remedy under this Agreement or
otherwise,  or delay by a party in  exercising  such right or remedy,  shall not
operate as a waiver thereof.

(d) The laws of the State of Delaware  shall  govern all issues  concerning  the
relative rights of the Company and the Investors as its stockholders.  All other
questions concerning the construction,  validity, enforcement and interpretation
of this  Agreement  shall be governed by the  internal  laws of the State of New
Jersey,  without giving effect to any choice of law or conflict of law provision
or rule  (whether  of the State of New  Jersey or any other  jurisdiction)  that
would cause the application of the laws of any jurisdiction other than the State
of New  Jersey.  Each party  hereby  irrevocably  submits  to the  non-exclusive
jurisdiction  of the  Superior  Courts of the State of New  Jersey,  sitting  in
Hudson  County,  New Jersey and  federal  courts for the  District of New Jersey
sitting Newark,  New Jersey, for the adjudication of any dispute hereunder or in
connection  herewith or with any  transaction  contemplated  hereby or discussed
herein,  and hereby  irrevocably  waives,  and agrees not to assert in any suit,
action  or  proceeding,  any  claim  that it is not  personally  subject  to the
jurisdiction of any such court,  that such suit, action or proceeding is brought
in an inconvenient forum or that the venue of such suit, action or proceeding is
improper.  Each party hereby  irrevocably waives personal service of process and
consents  to process  being  served in any such suit,  action or  proceeding  by
mailing a copy thereof to such party at the address for such notices to it under
this Agreement and agrees that such service shall constitute good and sufficient
service of process and notice thereof.  Nothing contained herein shall be deemed
to limit in any way any right to serve  process in any manner  permitted by law.
If any  provision of this  Agreement  shall be invalid or  unenforceable  in any
jurisdiction,  such invalidity or unenforceability shall not affect the validity
or enforceability of the remainder of this Agreement in that jurisdiction or the
validity or  enforceability  of any  provision  of this  Agreement  in any other
jurisdiction.  EACH PARTY HEREBY  IRREVOCABLY  WAIVES ANY RIGHT IT MAY HAVE, AND
AGREES  NOT TO  REQUEST,  A JURY  TRIAL  FOR  THE  ADJUDICATION  OF ANY  DISPUTE
HEREUNDER  OR IN  CONNECTION  HEREWITH OR ARISING OUT OF THIS  AGREEMENT  OR ANY
TRANSACTION CONTEMPLATED HEREBY.

(e) This Agreement, the Irrevocable Transfer Agent Instructions,  the Securities
Purchase Agreement and related documents  including the Series E Preferred Stock
and the Escrow  Agreement  dated the date hereof by and among the  Company,  the
Investors set forth on the Schedule of Investors  attached hereto and the Escrow
Agreement) constitute the entire agreement among the parties hereto with respect
to the subject matter hereof and thereof.  There are no restrictions,  promises,
warranties or undertakings, other than those set forth or referred to herein and
therein.  This  Agreement,  the  Irrevocable  Transfer Agent  Instructions,  the
Securities  Purchase  Agreement  and related  documents  including  the Series E
Preferred  Stock and the Escrow  Agreement  supersede all prior  agreements  and
understandings  among the  parties  hereto with  respect to the  subject  matter
hereof and thereof.

(f)  This  Agreement  shall  inure to the  benefit  of and be  binding  upon the
permitted successors and assigns of each of the parties hereto.

(g) The headings in this  Agreement are for  convenience  of reference  only and
shall not limit or otherwise affect the meaning hereof.

(h) This  Agreement  may be executed in  identical  counterparts,  each of which
shall be deemed an original but all of which shall  constitute  one and the same
agreement.  This  Agreement,  once executed by a party,  may be delivered to the
other party hereto by facsimile transmission of a copy of this Agreement bearing
the signature of the party so delivering this Agreement.

(i) Each party shall do and perform, or cause to be done and performed, all such
further  acts  and  things,  and  shall  execute  and  deliver  all  such  other
agreements,  certificates,  instruments  and  documents,  as the other party may
reasonably  request in order to carry out the intent and accomplish the purposes
of this Agreement and the consummation of the transactions contemplated hereby.

The language used in this Agreement will be deemed to be the language  chosen by
the parties to express their mutual  intent and no rules of strict  construction
will be applied against any party.

(j) This  Agreement is intended for the benefit of the parties  hereto and their
respective  permitted successors and assigns, and is not for the benefit of, nor
may any provision hereof be enforced by, any other Person.


                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]










         IN WITNESS WHEREOF, the parties have caused this Investor Registration
Rights Agreement to be duly executed as of day and year first above written.

                                    COMPANY:
                                    AVITAR, INC.

                                    By:__________________________________
                                    Name:     Peter P. Phildius
                                    Title:   CEO










                                   SCHEDULE I


                               SCHEDULE OF BUYERS




                                                                                               Address/Facsimile
              Name                                    Signature                                 Number of Buyer
                                                                                 
Cornell Capital Partners, LP       By:      Yorkville Advisors, LLC                 101 Hudson Street - Suite 3700
                                   Its:     General Partner                         Jersey City, NJ  07303
                                                                                    Facsimile:        (201) 985-8266

                                   By:
                                   Name:    Mark A. Angelo
                                   Its:     Portfolio Manager







                                    EXHIBIT A

                         FORM OF NOTICE OF EFFECTIVENESS
                            OF REGISTRATION STATEMENT



         Re:      AVITAR, INC

Ladies and Gentlemen:

     We are counsel to Avitar, Inc., a Delaware corporation (the "Company"), and
have represented the Company in connection with that certain Securities Purchase
Agreement (the "Purchase  Agreement")  entered into by and among the Company and
the investors named therein  (collectively,  the "Investors")  pursuant to which
the Company issued to the Investors  shares of its Common Stock, par value $0.01
per share (the "Common Stock").  Pursuant to the Purchase Agreement, the Company
also has entered into a  Registration  Rights  Agreement with the Investors (the
"Registration  Rights  Agreement")  pursuant to which the Company agreed,  among
other  things,  to  register  the  Registrable  Securities  (as  defined  in the
Registration Rights Agreement) under the Securities Act of 1933, as amended (the
"1933 Act"). In connection with the Company's obligations under the Registration
Rights  Agreement,  on  ____________  ____,  the  Company  filed a  Registration
Statement  on Form  ________  (File No.  333-_____________)  (the  "Registration
Statement")  with the  Securities  and Exchange SEC (the "SEC")  relating to the
Registrable   Securities  which  names  each  of  the  Investors  as  a  selling
stockholder there under.

     In connection with the foregoing,  we advise you that a member of the SEC's
staff has advised us by  telephone  that the SEC has entered an order  declaring
the  Registration  Statement  effective  under  the 1933 Act at  [ENTER  TIME OF
EFFECTIVENESS] on [ENTER DATE OF EFFECTIVENESS] and we have no knowledge,  after
telephonic  inquiry  of a  member  of the  SEC's  staff,  that  any  stop  order
suspending its  effectiveness  has been issued or that any  proceedings for that
purpose  are  pending  before,  or  threatened  by, the SEC and the  Registrable
Securities  are  available  for  resale  under  the  1933  Act  pursuant  to the
Registration Statement.

                            Very truly yours,



                            By:
                               -----------------------------------------------

cc:      [LIST NAMES OF Investors]