O.S. Engines 21503000 Cylinder and Piston for .15 CV FEATURES: Replaces worn cylinder and piston assemblies; Cylinder is constructed of brass with Nickel plating, piston is made of aluminum INCLUDES: One Cylinder and one Piston for the O;S; Max ;15CV-X, ;15LD-X, and the ;15CV-M and MX Engines REQUIRES: Disassembling engine and heating crankcase to remove old cylinder and piston assembly; Installing Cylinder so that alignment notch fits over