This is a replacement part for the O.S. FT-300 twin cylinder four-stroke / engine. / / This Package Includes: / (2) Head gaskets - this is the thin metal gasket that seals the gap between / the crankcase and cylinder head and also sets the head gap. / / Specifications: / Inner Diameter: 33.5mm (1.32") / Outer Diameter: 39.5mm (1.56") / Thickness: .430mm (.0169") / / JBN 4.4.94 *8)