This specification covers a butyl (IIR) rubber in the form of sheet, strip, tubing, extrusions, and molded shapes.

This product has been used typically for parts, such as O-rings, gaskets, grommets, and seals, requiring resistance to phosphate esters or low permeability to gases, but usage is not limited to such applications. Not suitable for use in contact with petroleum-base fluids due to excessive swell.