Piston Kit 24503A 24503APiston Kit (Cast Race)Race Cast piston developed with Vertex technology and race shape profile All pistons are heat treated with a T 5 hardening and tempering cycle All piston skirts are coated with a high tech Molybdenum Disulphite coating for faster break in time and increased piston life Cast piston kits are gravity cast aluminum alloy (not forged) with 18% silicone content, which produces an extremely light but very strong piston Kits include