Cometic 62-64 MG MGB BMC 1.8L B-Series 83mm Bore .070in MLS Cylinder Head GasketThe HP shim technology increases clampload around the combustion chamber, thereby increasing the sealability of the head gasket around the open deck block. The embossed outer layers of the gaskets meet the demands of a variety of harsh sealing environments, load conditions, and surface finishes The center or shim layer is an uncoated stainless steel layer which can be varied to accommodate multiple thickness requirements Requires less clamp load