June 24, 2003



To The Hercules Shareholders' Committee for NEW Management
17 State Street
New York, NY  10004


         While we have no intention of making a proposal to acquire Hercules, in
order to avoid any  possible  conflict of interest or even the  appearance  of a
possible  conflict,  the undersigned and our respective  affiliates (the "Heyman
parties"),  hereby agree,  subject to the Committee's  nominees being elected to
Hercules' Board of Directors,  to support and abide by the following  procedural
safeguards  in  connection  with any future  acquisition  proposal  made for the
Company.

         o    In the event that any acquisition proposal is made for Hercules by
              the Heyman parties:

              o   The Heyman  parties  would  support the formation of a Special
                  Committee  to respond to and, if  appropriate,  negotiate  any
                  acquisition  proposal.  The Special Committee would consist of
                  solely independent and disinterested directors, represented by
                  independent financial advisors and legal counsel.

              o   The Heyman parties would not pursue any  acquisition  proposal
                  for Hercules that is not recommended by the Special Committee.

              o   The Heyman  parties  would only  proceed  with an  acquisition
                  transaction  for  Hercules if approved  by  two-thirds  of the
                  shares (excluding those shares owned by the Heyman parties).

              o   The Heyman  parties  would  support a competing  proposal by a
                  third party if the Special  Committee  decides the third party
                  proposal is superior.

         o    In the  event a third  party  makes an  acquisition  proposal  for
              Hercules and the Heyman parties have not:

              o   The Heyman parties would tender all shares  beneficially owned
                  by them  into any  tender  or  exchange  offer,  if  Hercules'
                  disinterested   and  independent   directors   recommend  that
                  shareholders accept such offer; and


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              o   If any vote of  Hercules  shareholders  is held in  connection
                  with a third party  acquisition  proposal,  the Heyman parties
                  would vote all shares  beneficially  owned by them in the same
                  proportion as the votes of the other Hercules shareholders.



                                   Sincerely,


International Specialty Products Inc.



By:     /s/ Sunil Kumar                               /s/Samuel J. Heyman
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        Sunil Kumar                                   Samuel J. Heyman
        Chief Executive Officer



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