Vertex Top End Piston Kit With Gaskets. New T-box forgings and DLC coated wrist pins on forged pistons with highest compression ratios for increased strength and performance. All piston skirts are coated with a high-tech Molybdenum Disulfide 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. Forged pistons are forged from 2618 aluminum for superior strength and durability. Forged High Compression pistons improve power and torque across entire RPM range. Forged Replica pistons are forged O.E. replacements. All pistons are heat treated with a T-5 hardening and tempering cycle. Replica KTM 2-stroke pistons are factory supplied to KTM. All rings are O.E.M. replacements.