Manufactured by Namura Kit includes piston, rings, pin, clips, wrist pin bearing top end gasket kit you get exactly what is pictured 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 .040 over bore size 81.00mm Piston is 80.95mm Made in Taiwan Fits 1990 Polaris Trail Boss 350L 2x4 1990 Polaris Trail Boss 350L 4x4 1991 Polaris Trail Boss 350L 2x4 1991 Polaris Trail Boss 350L 4x4 1992 Polaris Trail Boss 350L 2x4 1992 Polaris Trail Boss 350L 4x4 1993 Polaris 350L 2x4 1993 Polaris 350L 4x4 1993 Polaris 350L 6x6 1993 Polaris Sportsman 400 4x4