Manufactured by Namura Kit includes piston, rings, pin, clips, top end gasket kit you get exactly what is pictured HyperDryve Series piston 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. Cast piston has super-high silicone content for additional strength Piston skirts are Molybdenium Teflon coated to minimize resistance/wear and provide extended life 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 76.80mm Size B piston is 76.77mm Compression ratio of 13.2 1 Made in Taiwan Fits 2010 Honda CRF250R 2011 Honda CRF250R 2012 Honda CRF250R 2013 Honda CRF250R