VERTEX 2-stroke pistons are cast from an aluminum alloy containing 18% silicon through gravity casting. The addition of silicon reduces thermal expansion at operating temperature. This advantage makes the piston less prone to rattling and fracture. Furthermore, silicon enhances the piston's wear properties, thereby extending its lifespan. This piston kit comes complete with piston ring(s), piston pin, and piston pin clip. The 2-stroke piston configurations are: Replica - piston matches the original form, Race - performance-enhancing piston design, Pro Race - forged special piston.