Manufactured by Namura HyperDryve Series piston Kit Includes piston, rings, pin, clips, top end gasket kit you get exactly what is pictured The HyperDryve line of pistons is composed of a space-age hypereutectic aluminum alloy developed by NASA. Engineered to maintain its high tensile strength up to 700 F 370 C , 50% higher than a conventional cast piston, this gives HyperDryve pistons the strength to perform under operating conditions normally reserved for forged pistons. Piston skirts are Molybdenium Teflon coated to minimize resistance/wear and provide extended life. Also allows for smoother start-ups break-ins. Piston dome is anodized for superior heat resistance and longer lifespan Namura gaskets use performance materials to increase durability and provide greater reliability Includes all gaskets pictured to rebuild top end Kit is for standard bore size 97.00mm Size C piston is 96.97mm 12.5 1 Compression ratio Made in Taiwan Fits 2010 Yamaha YZ450F 2011 Yamaha YZ450F 2012 Yamaha YZ450F 2013 Yamaha YZ450F