Athena Complete Gasket Kit P400210850205 Athena has specifically designed this RACE GASKET for the Pro, Semi-pro and Amateur riders who freshen up their engine prior to a race series or during mid-season. The kit will include a top of the line MLSS (Multi Layer Stainless Steel) Head Gasket and two premium quality base gaskets, one of which has a reduced thickness of 0.1 mm, to optimize engine compression ratios. This new composition gives the rider/technician a choice to increase compression and decrease the squish in order to get better performances. It is all in one kit! Our RACE GASKET kits are very competitively priced and supplied in a captivating packaging. These are sure to be a strong seller in the marketplace! Kit includes all necessary top quality gaskets, rubber parts and valve stem seals for a complete top end rebuild. Kit includes all paper gaskets and head O-ring (2-stroke). Does not include rubber shaped gaskets and valve stem seals. Kit includes all necessary gaskets, rubber parts and valve stem seals to rebuild engine Athena Complete Reduced Kit. Kit includes all paper gaskets, head O-rings (2-strokes) and all engine oils seals. Does not include rubber shaped gaskets and valve stem seals.