DESIG1.1 This specification applies to those elastomeric cellular materials of a firm grade that are manufactured in preformed shapes for use as gaskets and for use as sealing materials, in the form of compression seals or gaskets, or both, This specification covers elastomeric cellular preformed gasket and sealing materials. Elastomeric cellular materials shall be manufactured from natural rubber, synthetic rubber, rubber-like materials, or mixture of these, with added compounding ingred