Abstract: A method of producing a custom-fitting article such as a custom-fitting footbed (for example, a removable insole), a custom-fitting hand grip, a custom-fitting body pad, and a custom-fitting orthopedic cast. A member for producing same and a composition for use in connection therewith are also provided. A member, such as a gel pad or gel-filled envelope, is provided which comprises a body of formable material having a minimum setting temperature greater than 130.degree. F. and being setable by heating for a period not exceeding 30 minutes and subsequent cooling. The member is conformed by biasing it against a body part of a person or mammal with sufficient pressure to conform the member to the shape of the body part. The member is then heated for a period not exceeding 30 minutes and thereafter cooled so that the formable material is set and the member remains flexible while resiliently retaining an impression of the body part.