Manufactured by SPI Includes 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 85.00mm ***Pistons are made with anti-detonation grooves on intake and exhaust side, compared to exhaust side only on OEM piston*** Fits 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 2013 Polaris 800 Pro RMK 155 2013 Polaris 800 Pro RMK 163 2013 Polaris 800 RMK 155 2013 Polaris 800 RMK Assault 155 2013 Polaris 800 Rush 2013 Polaris 800 Rush Pro-R 2013 Polaris 800 Switchback 2013 Polaris 800 Switchback Assault 144 2013 Polaris 800 Switchback Pro-R 2014 Polaris 800 Indy SP 2014 Polaris 800 Pro RMK 155 2014 Polaris 800 Pro RMK 163 2014 Polaris 800 RMK 155 2014 Polaris 800 RMK Assault 155 2014 Polaris 800 RMK Assault 163 2014 Polaris 800 Rush Pro-R 2014 Polaris 800 Switchback 2014 Polaris 800 Switchback Adventure 2014 Polaris 800 Switchback Assault 2014 Polaris 800 Switchback Pro-R 2015 Polaris 800 Indy SP 2015 Polaris 800 Pro RMK 155 2015 Polaris 800 Pro RMK 163 2015 Polaris 800 RMK 155 2015 Polaris 800 RMK 163 2015 Polaris 800 RMK Assault 155 2015 Polaris 800 Rush Pro-S 2015 Polaris 800 Rush Pro-X 2015 Polaris 800 Switchback Assault 144 2015 Polaris 800 Switchback Pro-S 2015 Polaris 800 Switchback Pro-X 2016 Polaris 800 Pro RMK 155 AXYS 2016 Polaris 800 Pro RMK 163 AXYS 2016 Polaris 800 RMK Assault 155 2016 Polaris 800 Rush Pro-S 2016 Polaris 800 Rush Pro-X 2016 Polaris 800 SKS AXYS 155 2016 Polaris 800 Switchback Adventure 2016 Polaris 800 Switchback Assault 2016 Polaris 800 Switchback Pro-S 2016 Polaris 800 Switchback Pro-X