Exhibit 4.2

THIS  WARRANT  HAS NOT BEEN  REGISTERED  UNDER THE  SECURITIES  ACT OF 1933,  AS
AMENDED (THE "SECURITIES ACT") OR ANY OTHER APPLICABLE STATE SECURITIES LAWS AND
HAS BEEN ISSUED IN RELIANCE UPON  REGULATION D PROMULGATED  UNDER THE SECURITIES
ACT. THIS WARRANT SHALL NOT CONSTITUTE AN OFFER TO SELL NOR A SOLICITATION OF AN
OFFER TO BUY THE WARRANT IN ANY JURISDICTION IN WHICH SUCH OFFER OR SOLICITATION
WOULD BE UNLAWFUL.

THIS WARRANT MAY NOT BE SOLD,  PLEDGED,  TRANSFERRED OR ASSIGNED EXCEPT PURSUANT
TO AN  EFFECTIVE  REGISTRATION  STATEMENT  UNDER  THE  SECURITIES  ACT AND UNDER
APPLICABLE  STATE  SECURITIES  LAWS,  OR IN A  TRANSACTION  WHICH IS EXEMPT FROM
REGISTRATION  UNDER THE PROVISIONS OF THE SECURITIES ACT AND UNDER PROVISIONS OF
APPLICABLE STATE  SECURITIES LAWS; AND IN THE CASE OF AN EXEMPTION,  ONLY IF THE
COMPANY  HAS  RECEIVED  AN  OPINION OF COUNSEL  THAT SUCH  TRANSACTION  DOES NOT
REQUIRE  REGISTRATION  OF THE WARRANT,  WHICH OPINION AND WHICH COUNSEL SHALL BE
SATISFACTORY TO THE COMPANY IN ITS SOLE DISCRETION.

No. __

                                    WARRANT A

                  To Purchase ______ Shares of Common Stock of

                              XYBERNAUT CORPORATION


           THIS CERTIFIES that, for value received,  _____________________  (the
"Investor"),  is  entitled,  upon  the  terms  and  subject  to  the  conditions
hereinafter  set forth, at any time on or after October 15, 1998 and on or prior
to October 15, 2003 (the  "Termination  Date") but not thereafter,  to subscribe
for and purchase from XYBERNAUT CORPORATION,  a corporation  incorporated in the
State of Delaware (the  "Company"),  ____________  ____________  (______) shares
(the  "Warrant  Shares")  of Common  Stock,  par value US $0.01 per share of the
Company (the "Common  Stock").  The purchase  price of one share of Common Stock
(the  "Exercise  Price") under this Warrant shall be equal to $1.76 The Exercise
Price and the number of shares for which the  Warrant  is  exercisable  shall be
subject to  adjustment  as  provided  herein.  This  Warrant is being  issued in
connection  with the Private Equity Line Of Credit  Agreement  dated on or about
April 13, 1998 (the "Agreement"), and is subject to its terms and conditions. In
the event of any conflict  between the terms of this Warrant and the  Agreement,
the Agreement shall control.






           1.         Title of  Warrant.  Prior  to the  expiration  hereof  and
subject  to  compliance  with  applicable  laws,  this  Warrant  and all  rights
hereunder are transferable,  in whole or in part, at the office or agency of the
Company  by the holder  hereof in person or by duly  authorized  attorney,  upon
surrender of this  Warrant  together  with the  Assignment  Form annexed  hereto
properly endorsed.

           2.         Authorization  of Shares.  The Company  covenants that all
shares  of  Common  Stock  which  may be  issued  upon the  exercise  of  rights
represented  by this Warrant will,  upon exercise of the rights  represented  by
this Warrant, be duly authorized,  validly issued,  fully paid and nonassessable
and free from all taxes,  liens and  charges  in  respect  of the issue  thereof
(other than taxes in respect of any transfer  occurring  contemporaneously  with
such issue).

                      Exercise  of  Warrant.  Except as  provided  in  Section 4
below,  exercise of the purchase rights  represented by this Warrant may be made
at any time or times,  before the close of business on the Termination  Date, or
such  earlier  date on which this  Warrant  may  terminate  as  provided in this
Warrant,  by the  surrender  of this  Warrant  and the Notice of  Exercise  Form
annexed hereto duly executed, at the office of the Company (or such other office
or agency of the  Company  as it may  designate  by  notice  in  writing  to the
registered holder hereof at the address of such holder appearing on the books of
the  Company)  and upon  payment of the  Exercise  Price of the  shares  thereby
purchased;  whereupon  the holder of this Warrant shall be entitled to receive a
certificate for the number of shares of Common Stock so purchased.  Certificates
for shares  purchased  hereunder  shall be delivered to the holder hereof within
three (3)  business  days after the date on which this  Warrant  shall have been
exercised as  aforesaid.  Payment of the Exercise  Price of the shares may be by
certified check or cashier's check or by wire transfer to an account  designated
by the Company in an amount equal to the Exercise Price multiplied by the number
of Warrant Shares.

           4.         No Fractional  Shares or Scrip.  No  fractional  shares or
scrip  representing  fractional shares shall be issued upon the exercise of this
Warrant.

           5.         Charges, Taxes and Expenses.  Issuance of certificates for
shares of Common Stock upon the  exercise of this Warrant  shall be made without
charge to the holder  hereof for any issue or transfer  tax or other  incidental
expense in respect of the issuance of such  certificate,  all of which taxes and
expenses shall be paid by the Company,  and such certificates shall be issued in
the  name of the  holder  of this  Warrant  or in such  name or  names as may be
directed by the holder of this  Warrant;  provided,  however,  that in the event
certificates  for  shares of Common  Stock are to be issued in a name other than
the name of the  holder of this  Warrant,  this  Warrant  when  surrendered  for
exercise  shall be  accompanied  by the  Assignment  Form  attached  hereto duly
executed by the holder  hereof;  and  provided  further,  that upon any transfer
involved in the  issuance or delivery of any  certificates  for shares of Common
Stock,  the Company may require,  as a condition  thereto,  the payment of a sum
sufficient to reimburse it for any transfer tax incidental thereto.


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           6.         Closing  of  Books.   The  Company   will  not  close  its
shareholder books or records in any manner which prevents the timely exercise of
this Warrant for a period of time in excess of five (5) trading days per year.

           7.         No Rights as Shareholder until Exercise. This Warrant does
not  entitle  the  holder  hereof  to any  voting  rights  or other  rights as a
shareholder of the Company prior to the exercise thereof.  Upon the surrender of
this Warrant and the payment of the aggregate Exercise Price, the Warrant Shares
so  purchased  shall be and be deemed to be issued to such  holder as the record
owner of such  shares  as of the close of  business  on the later of the date of
such surrender or payment.

           8.         Assignment  and  Transfer of Warrant.  This Warrant may be
assigned by the surrender of this Warrant and the Assignment Form annexed hereto
duly  executed at the office of the  Company (or such other  office or agency of
the Company as it may  designate by notice in writing to the  registered  holder
hereof at the address of such holder appearing on the books of the Company).

           9.         Loss,  Theft,  Destruction  or Mutilation of Warrant.  The
Company  represents  and  warrants  that upon receipt by the Company of evidence
reasonably  satisfactory to it of the loss, theft,  destruction or mutilation of
this  Warrant  certificate  or any stock  certificate  relating  to the  Warrant
Shares,  and in case of loss,  theft or  destruction,  of  indemnity or security
reasonably  satisfactory  to it, and upon  surrender  and  cancellation  of such
Warrant or stock certificate,  if mutilated, the Company will make and deliver a
new  Warrant  or  stock   certificate  of  like  tenor  and  dated  as  of  such
cancellation, in lieu of such Warrant or stock certificate.

           10.        Saturdays,   Sundays,   Holidays,  etc.  If  the  last  or
appointed  day for the  taking  of any  action  or the  expiration  of any right
required or granted herein shall be a Saturday,  Sunday or a legal holiday, then
such action may be taken or such right may be exercised  on the next  succeeding
day not a legal holiday.

           11.        Effect of Certain Events.

           (a)        If at  any  time  the  Company  proposes  (i) to  sell  or
otherwise  convey  all or  substantially  all of its  assets or (ii) to effect a
transaction  (by merger or otherwise) in which more than 50% of the voting power
of the Company is disposed of (collectively, a "Sale or Merger Transaction"), in
which the  consideration  to be  received  by the  Company  or its  shareholders
consists solely of cash, then the Warrant shall terminate if the Warrant has not
been exercised by the effective date of such transaction, the Company shall give
the holder of this Warrant thirty (30) days' notice of such  termination  and of
the proposed effective date of the transaction.

           (b)        In case the  Company  shall  at any time  effect a sale or
merger  transaction in which the  consideration to be received by the Company or
its shareholders  consists in part of consideration  other than cash, the holder
of this Warrant shall have the right thereafter to purchase, by exercise of this
Warrant and payment of the aggregate  Exercise Price in effect immediately prior
to such action,  the kind and amount of shares and other securities and property
which it would have owned or have been  entitled to receive  after the happening
of such transaction had this Warrant been exercised immediately prior thereto.

           The Company  agrees that the Warrant  Shares shall be included in the
Registration Statement to be filed by the Company pursuant to the Private Equity
Line Of Credit Agreement dated as of April 13, 1998.



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           12.        Adjustments  of  Exercise  Price  and  Number  of  Warrant
Shares. The number and kind of securities  purchasable upon the exercise of this
Warrant and the Exercise Price shall be subject to adjustment  from time to time
upon the happening of any of the following.

           In case the Company  shall (i) declare or pay a dividend in shares of
Common Stock or make a distribution  in shares of Common Stock to holders of its
outstanding Common Stock, (ii) subdivide its outstanding shares of Common Stock,
(iii) combine its  outstanding  shares of Common Stock into a smaller  number of
shares  of Common  Stock or (iv)  issue any  shares  of its  capital  stock in a
reclassification  of the  Common  Stock,  then  the  number  of  Warrant  Shares
purchasable  upon  exercise of this Warrant  immediately  prior thereto shall be
adjusted  so that the holder of this  Warrant  shall be  entitled to receive the
kind and number of Warrant  Shares or other  securities  of the Company which he
would  have  owned or have  been  entitled  to  receive  had such  Warrant  been
exercised in advance  thereof.  Upon each such adjustment of the kind and number
of Warrant  Shares or other  securities  of the  Company  which are  purchasable
hereunder,  the holder of this Warrant shall  thereafter be entitled to purchase
the number of Warrant Shares or other securities  resulting from such adjustment
at an  Exercise  Price per such  Warrant  Share or other  security  obtained  by
multiplying the Exercise Price in effect immediately prior to such adjustment by
the number of Warrant Shares  purchasable  pursuant hereto  immediately prior to
such adjustment and dividing by the number of Warrant Shares or other securities
of the Company  resulting from such  adjustment.  An adjustment made pursuant to
this paragraph shall become  effective  immediately  after the effective date of
such event retroactive to the record date, if any, for such event.


           13.        Voluntary  Adjustment  by the Company.  The Company may at
any time during the term of this Warrant, reduce the then current Exercise Price
to any  amount  and for any period of time  deemed  appropriate  by the Board of
Directors of the Company.

           14.        Notice of  Adjustment.  Whenever  the  number  of  Warrant
Shares or number or kind of securities or other  property  purchasable  upon the
exercise of this Warrant or the Exercise Price is adjusted,  as herein provided,
the Company shall promptly mail by registered or certified mail,  return receipt
requested,  to  the  holder  of  this  Warrant  notice  of  such  adjustment  or
adjustments  setting forth the number of Warrant Shares (and other securities or
property)  purchasable  upon the exercise of this Warrant and the Exercise Price
of such Warrant Shares (and other securities or property) after such adjustment,
setting  forth a brief  statement of the facts  requiring  such  adjustment  and
setting forth the computation by which such adjustment was made. Such notice, in
absence of manifest  error,  shall be conclusive  evidence of the correctness of
such adjustment.

           15.        Authorized  Shares.  The Company covenants that during the
period the Warrant is  outstanding,  it will  reserve  from its  authorized  and
unissued Common Stock a sufficient  number of shares to provide for the issuance
of the  Warrant  Shares  upon the  exercise of any  purchase  rights  under this
Warrant.  The Company further  covenants that its issuance of this Warrant shall
constitute  full  authority  to its  officers  who are charged  with the duty of
executing stock certificates to execute and issue the necessary certificates for
the Warrant Shares upon the exercise of the purchase  rights under this Warrant.
The Company will take all such  reasonable  action as may be necessary to assure
that such Warrant Shares may be issued as provided  herein without  violation of
any applicable law or regulation, or of any requirements of the NASDAQ Small Cap
Stock Market or any domestic securities exchange upon which the Common Stock may
be listed.

           16.        Call/Forced  Exercise.  The  Company,  at its option,  may
redeem this  Warrant for $0.01 per  Warrant  Share by giving the Holder  written
notice  (the "Call  Notice")  at any time after the  Registration  Statement  is
declared effective, and the closing Bid Price of the Common Stock of the Company
is greater than


                                       4




one  hundred  fifty  (150%)  percent  of the  Exercise  Price  for  twenty  (20)
consecutive Trading Days. To be effective,  the Call Notice must be given within
three (3) Trading Days after the  aforementioned  twenty day period.  The rights
and privileges granted pursuant to this Warrant shall terminate thirty (30) days
after the Call  Notice is sent to the  Holder if the  warrant  is not  exercised
during that  period.  In the event the Warrants  are not  exercised  during this
period the Company  will remit to the Holder  $0.01 per  Warrant  Share upon the
Holder tendering to the Company the expired Warrant certificate.

           17.        Miscellaneous.

           (a)        Issue Date;  Jurisdiction.  The provisions of this Warrant
shall be  construed  and shall be given effect in all respects as if it had been
issued and  delivered by the Company on the date hereof.  This Warrant  shall be
binding  upon any  successors  or assigns of the  Company.  This  Warrant  shall
constitute a contract  under the laws of New York without regard to its conflict
of law, principles or rules, and be subject to arbitration pursuant to the terms
set forth in the Agreement.

           (b)        Restrictions.  The  holder  hereof  acknowledges  that the
Warrant Shares  acquired upon the exercise of this Warrant,  if not  registered,
will have restrictions upon resale imposed by state and federal securities laws.
Each  certificate  representing  the  Warrant  Shares  issued to the Holder upon
exercise will bear the following legend:

            "THE  SECURITIES   EVIDENCED  BY  THIS  CERTIFICATE  HAVE  NOT  BEEN
      REGISTERED  UNDER  THE  U.S.  SECURITIES  ACT OF  1933,  AS  AMENDED  (THE
      "SECURITIES  ACT"), OR ANY OTHER APPLICABLE  SECURITIES LAWS AND HAVE BEEN
      ISSUED IN RELIANCE UPON AN EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF
      THE SECURITIES ACT AND SUCH OTHER SECURITIES  LAWS.  NEITHER THIS SECURITY
      NOR ANY INTEREST OR PARTICIPATION HEREIN MAY BE REOFFERED, SOLD, ASSIGNED,
      TRANSFERRED,  PLEDGED, ENCUMBERED,  HYPOTHECATED OR OTHERWISE DISPOSED OF,
      EXCEPT  PURSUANT  TO  AN  EFFECTIVE   REGISTRATION   STATEMENT  UNDER  THE
      SECURITIES  ACT OR PURSUANT TO A  TRANSACTION  THAT IS EXEMPT FROM, OR NOT
      SUBJECT TO, SUCH REGISTRATION".

           (c)        Modification  and Waiver.  This Warrant and any provisions
hereof may be changed, waived, discharged or terminated only by an instrument in
writing signed by the party against which enforcement of the same is sought.

           (d)        Notices. Any notice, request or other document required or
permitted to be given or delivered to the holders hereof by the Company shall be
delivered or shall be sent by certified or registered mail, postage prepaid,  to
each such  holder at its  address as shown on the books of the Company or to the
Company at the address set forth in the Agreement.

           IN  WITNESS  WHEREOF,  the  Company  has  caused  this  Warrant to be
executed by its officer thereunto duly authorized.

Dated:  April ___, 1998
                                                    XYBERNAUT CORPORATION


                                                    By_________________________



                                       5






                               NOTICE OF EXERCISE



To:        XYBERNAUT CORPORATION



            (1)   The undersigned  hereby elects to purchase  ________ shares of
Common  Stock,  par  value  $ per  shares  (the  "Common  Stock")  of  XYBERNAUT
CORPORATION  pursuant to the terms of the attached Warrant, and tenders herewith
payment of the exercise  price in full,  together with all  applicable  transfer
taxes, if any.

            (2)   Please issue a certificate or certificates  representing  said
shares of Common Stock in the name of the  undersigned  or in such other name as
is specified below:

                  __________________________
                  (Name)

                  __________________________
                  (Address)
                  __________________________


            (3)   The shares of Common Stock being issued in connection with the
exercise of the attached  Warrant are [not] being issued in connection  with the
sale of the Common Stock.


Dated:


                                                      __________________________
                                                      Signature





                                       1







                                 ASSIGNMENT FORM

                    (To assign the foregoing warrant, execute
                   this form and supply required information.
                 Do not use this form to exercise the warrant.)



            FOR VALUE RECEIVED,  the foregoing  Warrant and all rights evidenced
thereby are hereby assigned to

_______________________________________________ whose address is

_________________________________________________________________.



_________________________________________________________________


                                                    Dated:  ______________, 1998


                Holder's Signature:            _____________________________

                Holder's Address:              _____________________________

                                               _____________________________



Signature Guaranteed:  ___________________________________________




NOTE: The signature to this  Assignment Form must correspond with the name as it
appears on the face of the Warrant,  without  alteration or  enlargement  or any
change whatsoever,  and must be guaranteed by a bank or trust company.  Officers
of  corporations  and  those  acting  in an  fiduciary  or other  representative
capacity  should  file  proper  evidence of  authority  to assign the  foregoing
Warrant.





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