The VERTEX 2-stroke pistons are manufactured using a gravity casting process from an aluminum alloy containing 18% silicon. The presence of silicon helps to reduce thermal expansion at operating temperatures. This results in pistons being less prone to rattling and breakage. Additionally, silicon enhances the wear resistance of the pistons, thereby extending their lifespan. The kit includes the piston, piston ring(s), piston pin, and piston pin circlips! Piston versions for 2-stroke engines include: Replica (standard form), Race (performance-enhancing), and Pro Race (forged special piston).