Manufactured by SPI Includes 2 pistons, ring sets, wrist pins, & circlips as pictured SPI pistons are engineered to provide the best possible path for combustion chamber heat transfer to the cylinder walls All SPI pistons, rings, pins, & circlips are manufactured to OEM specifications All individual components are interchangeable with original parts Piston weight is compatible with original piston T-Moly series with Teflon-Molybdenum coating T-Moly series pistons reduce friction, resist seizure, & improve durability Made in Taiwan Pistons are for standard bore size 76.00mm Fits most 2003-2015 Ski-Doo 550F (fan cooled) snowmobiles