Manufactured by SPI Includes 2 pistons, ring sets, wrist pins, circlips, bearings fix kit 2 base gaskets, aluminum spacer, 8 extra long cylinder bolts and 2 dowel alignment pins 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 85.00mm ***Dual ring design pistons*** Fits 2010 Polaris 800 Assault RMK 2010 Polaris 800 Dragon IQ 2010 Polaris 800 Dragon RMK 155 2010 Polaris 800 Dragon RMK 163 2010 Polaris 800 Dragon Switchback 2010 Polaris 800 IQ 2010 Polaris 800 RMK 144 2010 Polaris 800 RMK 155 2010 Polaris 800 Switchback 2011 Polaris 800 Pro RMK 155 2011 Polaris 800 Pro RMK 163 2011 Polaris 800 RMK 155 2011 Polaris 800 RMK Assault 155 2011 Polaris 800 Rush 2011 Polaris 800 Rush Pro-R 2011 Polaris 800 Switchback Assault 144 2012 Polaris 800 Pro RMK 155 2012 Polaris 800 Pro RMK 163 2012 Polaris 800 RMK 155 2012 Polaris 800 RMK Assault 155 2012 Polaris 800 Rush 2012 Polaris 800 Rush Pro-R 2012 Polaris 800 Rush Pro-R LE 2012 Polaris 800 Switchback 2012 Polaris 800 Switchback Assault 144 2012 Polaris 800 Switchback Pro-R