The VERTEX Race Evolution Piston is specifically designed for racing, making it the ultimate performance weapon among all pistons. VERTEX 2-stroke pistons are gravity cast from an aluminum alloy containing 18% silicon. The addition of silicon helps reduce thermal expansion during operating temperatures, making the piston less prone to rattling and breakage. Furthermore, silicon enhances the piston's wear resistance, thereby extending its lifespan. The VERTEX TopEnd Piston Kits include everything needed for a piston replacement, such as the piston, piston rings, piston pin bearing, retaining clips, and more. As an original equipment manufacturer (OEM) for some of the largest motorcycle brands, VERTEX is trusted by many factory teams in the MXGP for its high performance.