SUPPLEMENTAL INDENTURE


                  SUPPLEMENTAL INDENTURE (this "SUPPLEMENTAL INDENTURE"),  dated
as of March 31,  1998,  among  LICO,  Inc.,  a Missouri  corporation,  Automatic
Systems,  Inc.,  a  Missouri  corporation,  and LICO  Steel,  Inc.,  a  Missouri
corporation  (each a  "GUARANTEEING  SUBSIDIARY" and together the " GUARANTEEING
SUBSIDIARIES"),  subsidiaries of Columbus McKinnon Corporation (or its permitted
successor),  a New York  corporation  (the  "COMPANY"),  the Company,  the other
Guarantors  (as defined in the  Indenture  referred to herein) and State  Street
Bank and Trust Company,  N.A., as trustee under the indenture  referred to below
(the "TRUSTEE").

                               W I T N E S S E T H

                  WHEREAS,  the Company has heretofore executed and delivered to
the Trustee an indenture (the "INDENTURE"), dated as of March 31, 1998 providing
for the issuance of an aggregate  principal  amount of up to $300.0 million of 8
1/2% Senior Subordinated Notes due 2008 (the "NOTES");

                  WHEREAS,   the   Indenture   provides   that   under   certain
circumstances  the  Guaranteeing  Subsidiaries  shall execute and deliver to the
Trustee a supplemental indenture pursuant to which the Guaranteeing Subsidiaries
shall unconditionally guarantee all of the Company's Obligations under the Notes
and  the  Indenture  on the  terms  and  conditions  set  forth  herein  (each a
"SUBSIDIARY GUARANTEE" and together the "SUBSIDIARY GUARANTEES"); and

                  WHEREAS,  pursuant  to  Section  9.01  of the  Indenture,  the
Trustee is authorized to execute and deliver this Supplemental Indenture.

                                                                              
                  NOW THEREFORE, in consideration of the foregoing and for other
good and valuable  consideration,  the receipt of which is hereby  acknowledged,
the Guaranteeing  Subsidiary and the Trustee mutually covenant and agree for the
equal and ratable benefit of the Holders of the Notes as follows:

                  1. CAPITALIZED  TERMS.  Capitalized  terms used herein without
                  definition  shall have the  meanings  assigned  to them in the
                  Indenture.

                  2.  AGREEMENT  TO  GUARANTEE.  The  Guaranteeing  Subsidiaries
                  hereby agree as follows:

                  (a)      Along with all Guarantors named in the Indenture,  to
                           jointly and  severally  Guarantee to each Holder of a
                           Note  authenticated  and delivered by the Trustee and
                           to  the  Trustee  and  its  successors  and  assigns,
                           irrespective  of the validity and  enforceability  of
                           the  Indenture,  the Notes or the  obligations of the
                           Company hereunder or thereunder, that:

                           (i)      the  principal  of and interest on the Notes
                                    will be  promptly  paid in  full  when  due,
                                    whether  at   maturity,   by   acceleration,
                                    redemption or otherwise, and interest on the
                                    overdue  principal  of and  interest  on the
                                    Notes,  if any,  if  lawful,  and all  other
                                    obligations of the Company to the Holders or
                                    the Trustee  hereunder or thereunder will be
                                    promptly paid in full or  performed,  all in
                                    accordance   with  the  terms   hereof   and
                                    thereof; and

                           (ii)     in case of any  extension of time of payment
                                    or renewal of any Notes or any of such other
                                    obligations, that same will be promptly paid
                                    in full when due or performed in  accordance
                                    with the terms of the  extension or renewal,
                                    whether at stated maturity,  by acceleration
                                    or  otherwise.  Failing  payment when due of
                                    any amount so guaranteed or any  performance
                                    so  guaranteed  for  whatever  reason,   the
                                    Guarantors  shall be jointly  and  severally
                                    obligated to pay the same immediately.

                  (b)      The  obligations  hereunder  shall be  unconditional,
                           irrespective   of   the   validity,   regularity   or
                           enforceability  of the  Notes or the  Indenture,  the
                           absence of any action to enforce the same, any waiver
                           or consent by any Holder of the Notes with respect to
                           any provisions hereof or thereof, the recovery of any
                           judgment  against the Company,  any action to enforce
                           the  same  or  any  other  circumstance  which  might
                           otherwise  constitute a legal or equitable  discharge
                           or defense of a guarantor.


                  (c)      The   following   is   hereby    waived:    diligence
                           presentment, demand of payment, filing of claims with
                           a court in the event of  insolvency  or bankruptcy of
                           the Company,  any right to require a proceeding first
                           against the Company,  protest, notice and all demands
                           whatsoever.

                  (d)      These  Subsidiary  Guarantees shall not be discharged
                           except by  complete  performance  of the  obligations
                           contained in the Notes and the Indenture.

                  (e)      If any Holder or the Trustee is required by any court
                           or   otherwise   to  return  to  the   Company,   the
                           Guarantors, or any Custodian,  Trustee, liquidator or
                           other similar  official  acting in relation to either
                           the  Company or the  Guarantors,  any amount  paid by
                           either  to  the   Trustee  or  such   Holder,   these
                           Subsidiary  Guarantees,  to  the  extent  theretofore
                           discharged,  shall be  reinstated  in full  force and
                           effect.

                  (f)      The Guaranteeing  Subsidiaries  shall not be entitled
                           to  any  right  of  subrogation  in  relation  to the
                           Holders  in  respect  of any  obligations  guaranteed
                           hereby  until  payment  in  full  of all  obligations
                           guaranteed hereby.

                  (g)      As between the  Guarantors,  on the one hand, and the
                           Holders and the Trustee,  on the other hand,  (x) the
                           maturity of the obligations  guaranteed hereby may be
                           accelerated as provided in Article 6 of the Indenture
                           for the  purposes  of  these  Subsidiary  Guarantees,
                           notwithstanding   any  stay,   injunction   or  other
                           prohibition  preventing such  acceleration in respect
                           of the obligations  guaranteed hereby, and (y) in the
                           event  of any  declaration  of  acceleration  of such
                           obligations   as   provided   in  Article  6  of  the
                           Indenture,  such obligations  (whether or not due and
                           payable)  shall  forthwith  become due and payable by
                           the  Guarantors  for the purpose of these  Subsidiary
                           Guarantees.

                  (h)      The   Guarantors   shall   have  the  right  to  seek
                           contribution from any non-paying Guarantor so long as
                           the exercise of such right does not impair the rights
                           of the Holders under the Subsidiary Guarantees.

                  (i)      Notwithstanding  the  foregoing,  in the  event  that
                           these  Subsidiary   Guarantees  would  constitute  or
                           result in a violation  of any  applicable  fraudulent
                           conveyance   or   similar   law   of   any   relevant
                           jurisdiction,   the  liability  of  the  Guaranteeing
                           Subsidiaries  under this  Supplemental  Indenture and
                           their  Subsidiary  Guarantees shall be reduced to the
                           maximum  amount  permissible  under  such  fraudulent
                           conveyance or similar law.

                  3. SUBORDINATION.  Payment of principal,  premium, if any, and
                  interest and  Liquidated  Damages,  if any, on the  Subsidiary
                  Guarantees  is  subordinated  to the prior  payment in full of
                  Senior Debt on the terms provided in the Indenture.

                  4. EXECUTION AND DELIVERY. Each Guaranteeing Subsidiary agrees
                  that the Subsidiary  Guarantees shall remain in full force and
                  effect  notwithstanding  any failure to endorse on each Note a
                  notation of such Subsidiary Guarantee.

                  5. GUARANTEEING SUBSIDIARIES MAY CONSOLIDATE,  ETC. ON CERTAIN
                  TERMS.

                  (a)      The Guaranteeing Subsidiaries,  and each of them, may
                           not  consolidate  with or merge with or into (whether
                           or  not  such  Guarantor  is  the  surviving  Person)
                           another corporation,  Person or entity whether or not
                           affiliated with such Guarantor unless:

                           (i)      subject to Section  11.05 of the  Indenture,
                                    the Person  formed by or surviving  any such
                                    consolidation  or merger  (if  other  than a
                                    Guarantor  or the  Company)  unconditionally
                                    assumes   all   the   obligations   of  such
                                    Guarantor,   pursuant   to  a   supplemental
                                    indenture in form and  substance  reasonably
                                    satisfactory  to  the  Trustee,   under  the
                                    Notes,  the  Indenture  and  the  Subsidiary
                                    Guarantee  on the terms set forth  herein or
                                    therein; and

                           (ii)     immediately  after  giving  effect  to  such
                                    transaction,  no Default or Event of Default
                                    exists.

                  (b)      In case of any such  consolidation,  merger,  sale or
                           conveyance  and upon the  assumption by the successor
                           corporation, by supplemental indenture,  executed and
                           delivered to the Trustee and  satisfactory in form to
                           the Trustee,  of the  Subsidiary  Guarantee  endorsed
                           upon the Notes and the due and  punctual  performance
                           of  all  of  the  covenants  and  conditions  of  the
                           Indenture  to be  performed  by the  Guarantor,  such
                           successor   corporation   shall  succeed  to  and  be
                           substituted for the Guarantor with the same effect as
                           if it had been  named  herein  as a  Guarantor.  Such
                           successor  corporation  thereupon  may  cause  to  be
                           signed any or all of the Subsidiary  Guarantees to be
                           endorsed  upon all of the  Notes  issuable  hereunder
                           which  theretofore  shall not have been signed by the
                           Company  and  delivered  to  the  Trustee.   All  the
                           Subsidiary Guarantees so issued shall in all respects
                           have  the  same  legal  rank and  benefit  under  the
                           Indenture as the  Subsidiary  Guarantees  theretofore
                           and thereafter issued in accordance with the terms of
                           the  Indenture  as  though  all  of  such  Subsidiary
                           Guarantees  had  been  issued  at  the  date  of  the
                           execution hereof.

                  (c)      Except  as  set  forth  in  Articles  4 and 5 of  the
                           Indenture,  and  notwithstanding  clauses (a) and (b)
                           above,  nothing  contained in the Indenture or in any
                           of the  Notes  shall  prevent  any  consolidation  or
                           merger of a  Guarantor  with or into the  Company  or
                           another  Guarantor,  or  shall  prevent  any  sale or
                           conveyance  of  the  property  of a  Guarantor  as an
                           entirety  or  substantially  as an  entirety  to  the
                           Company or another Guarantor.

                  6. RELEASES.

                  (a)      In the event of a sale or other disposition of all of
                           the  assets  of any  Guarantor,  by  way  of  merger,
                           consolidation  or  otherwise,  or  a  sale  or  other
                           disposition  of  all  of  the  capital  stock  of any
                           Guarantor,  then  such  Guarantor  (in the event of a
                           sale  or  other   disposition,   by  way  of  merger,
                           consolidation  or  otherwise,  of all of the  capital
                           stock of such Guarantor) or the corporation acquiring
                           the  property  (in  the  event  of a  sale  or  other
                           disposition of all or substantially all of the assets
                           of such  Guarantor)  will be released and relieved of
                           any  obligations  under  its  Subsidiary   Guarantee;
                           PROVIDED  that the Net Proceeds of such sale or other
                           disposition   are  applied  in  accordance  with  the
                           applicable  provisions  of the  Indenture,  including
                           without  limitation,  Section 4.10 of the  Indenture.
                           Upon  delivery  by the  Company to the  Trustee of an
                           Officers'  Certificate  and an  Opinion of Counsel to
                           the effect  that such sale or other  disposition  was
                           made by the Company in accordance with the provisions
                           of  the  Indenture,   including  without   limitation
                           Section  4.10 of the  Indenture,  the  Trustee  shall
                           execute any documents reasonably required in order to
                           evidence  the  release  of  any  Guarantor  from  its
                           obligations under its Subsidiary Guarantee.

                  (b)      Any Guarantor not released from its obligations under
                           its Subsidiary  Guarantee shall remain liable for the
                           full amount of principal of and interest on the Notes
                           and for the other  obligations of any Guarantor under
                           the  Indenture  as  provided  in  Article  11 of  the
                           Indenture.

                  7. NO  RECOURSE  AGAINST  OTHERS.  No past,  present or future
                  director,  officer,  employee,  incorporator,  stockholder  or
                  agent of each of the Guaranteeing Subsidiaries, as such, shall
                  have any liability for any  obligations  of the Company or any
                  Guaranteeing   Subsidiary  under  the  Notes,  any  Subsidiary
                  Guarantees,  the Indenture or this  Supplemental  Indenture or
                  for any claim  based on, in respect  of, or by reason of, such
                  obligations  or their  creation.  Each  Holder of the Notes by
                  accepting a Note waives and releases all such  liability.  The
                  waiver and release are part of the  consideration for issuance
                  of the  Notes.  Such  waiver  may not be  effective  to  waive
                  liabilities  under the federal  securities  laws and it is the
                  view of the SEC that such a waiver is against public policy.

                  8. NEW YORK LAW TO GOVERN.  THE  INTERNAL  LAW OF THE STATE OF
                  NEW  YORK  SHALL   GOVERN  AND  BE  USED  TO   CONSTRUE   THIS
                  SUPPLEMENTAL INDENTURE BUT WITHOUT GIVING EFFECT TO APPLICABLE
                  PRINCIPLES  OF  CONFLICTS  OF  LAW  TO  THE  EXTENT  THAT  THE
                  APPLICATION  OF THE  LAWS OF  ANOTHER  JURISDICTION  WOULD  BE
                  REQUIRED THEREBY.

                  9. COUNTERPARTS.  The parties may sign any number of copies of
                  this  Supplemental  Indenture.  Each  signed  copy shall be an
                  original,   but  all  of  them  together  represent  the  same
                  agreement.

                  10. EFFECT OF HEADINGS.  The Section  headings  herein are for
                  convenience only and shall not affect the construction hereof.

                  11. THE TRUSTEE.  The Trustee shall not be  responsible in any
                  manner  whatsoever  for  or in  respect  of  the  validity  or
                  sufficiency  of  this  Supplemental  Indenture  or  for  or in
                  respect  of  the  recitals  contained  herein,  all  of  which
                  recitals are made solely by the Guaranteeing  Subsidiaries and
                  the Company.








         IN WITNESS  WHEREOF,  the parties hereto have caused this  Supplemental
Indenture  to be duly  executed  and  attested,  all as of the date first  above
written.

Dated:  March 31, 1998


                                    LICO, INC.


                                    By:   /s/Robert L. Montgomery
                                    Name:    Robert L. Montgomery
                                    Title:   Treasurer


                                    AUTOMATIC SYSTEMS, INC.


                                    By: /s/Robert L. Montgomery
                                    Name:  Robert L. Montgomery
                                    Title: Treasurer


                                    LICO STEEL, INC.


                                    By: /s/Robert L. Montgomery
                                    Name:  Robert L. Montgomery
                                    Title: Treasurer


                                    COLUMBUS McKINNON CORPORATION


                                    By: /s/Robert L. Montgomery
                                    Name:  Robert L. Montgomery
                                    Title: Executive Vice President


                                    YALE INDUSTRIAL PRODUCTS, INC.


                                    By: /s/Robert L. Montgomery
                                    Name:  Robert L. Montgomery
                                    Title: Treasurer


                                    MECHANICAL PRODUCTS, INC.


                                    By: /s/Robert L. Montgomery
                                    Name:  Robert L. Montgomery
                                    Title: Treasurer






                                    MINITEC CORPORATION


                                    By: /s/Robert L. Montgomery
                                    Name:  Robert L. Montgomery
                                    Title: Treasurer


                                    STATE STREET BANK AND TRUST COMPANY, N.A.
                                    as Trustee


                                    By: /s/James E. Murphy
                                    Name:  James E. Murphy
                                    Title: Vice President