Manufactured by Kit Includes piston, rings, pin, clips (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 Kit is for standard bore size – 68.00mm Piston is 67.94mm for size A cylinders Compression ratio of 10.6:1 Compatible with Yamaha models below: 1992 – 1998 YZ250 1992 – 1997 WR250