3-5/8" big bore. .022" RCM (Rubber Coated Metal). Final crush .020". RCM (Rubber Coated Metal) gaskets consists of a .020" thick stainless spring steel base covered with a .001" thick heat resistant Viton rubber on both sides. A very strong gasket which requires no re-torquing. Gaskets will not become brittle or burn out.
Fits: > 63-84 Big Twin (Excl. Evo) with 3-5/8" big bore cylinders (NU)
