All Wiseco Pistons are forged from high silicon, low expansion aluminum which offers superior strength, reduced weight, improved heat transfer, and longer life. Diamond turned finish from one of the many CNC computer controlled turning centers guarantees you a perfect finish with no size variation. Wiseco's wide range of oversize pistons increase the life of cast iron lined cylinders. Wiseco's state-of-the-art computerized manufacturing facility is dedicated to supplying both the high-perfomance racer and recreational enthusiast with the finest forged piston available in today's market place. Wiseco high performance forged pistons are designed from over 70 years of experience in all racing and riding conditions, to provide your engine with the best performance, durability, and long service life. All Wiseco pistons and components are optimized for your vehicle to get the most value for your money. *Please note pistons and rings sold by bore size. *STANDARD and OVERSIZES are not indicated. CONTENTS: 2638XC - 67.00 mm Ring Set CW16 - ROUND WIRE PIN LOCKS 16MM (PAIR) S256 - PistonPin 16mm x 2.047" NonChromed TW