VERTEX 2-stroke pistons are gravity cast from an aluminum alloy containing 18% silicon. The addition of silicon helps reduce thermal expansion at operating temperatures. This advantage makes the piston less prone to noise and fractures. Silicon also enhances the piston's wear resistance, thereby extending its lifespan. The piston kit includes the piston itself, piston rings, piston pin, and piston pin clip. The 2-stroke piston variants are as follows: Replica - piston matches the original shape, Race - performance-enhancing piston version, Pro Race - forged special piston.