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 .040 over bore size 73.00mm Fits 1979 Moto-Ski Grand Prix Special 1979 Ski-Doo Blizzard 5500 1980 Moto-Ski Futura 500 1980 Moto-Ski Grand Prix Special 1980 Ski-Doo Blizzard 5500 1980 Ski-Doo Everest 500 1981 Moto-Ski Futura 500 1981 Moto-Ski Grand Prix Special 1981 Ski-Doo Blizzard 5500 1981 Ski-Doo Everest 500 1982 Moto-Ski Futura 500 1982 Moto-Ski Sonic 1982 Ski-Doo Blizzard 5500 MX 1982 Ski-Doo Everest 500 1983 Moto-Ski Futura 500 1983 Ski-Doo Alpine 503 1983 Ski-Doo Blizzard 5500 MX 1983 Ski-Doo Everest 500 1984 Ski-Doo Alpine 503 1984 Ski-Doo Blizzard 5500 MX 1985 Ski-Doo Alpine 503 1985 Ski-Doo Formula Plus 503 1985 Ski-Doo Safari Grand Luxe 1986 Ski-Doo Alpine 503 1986 Ski-Doo Formula Plus 503 1986 Ski-Doo Safari 503 1987 Ski-Doo Alpine II 503 1987 Ski-Doo Escapade 503 1987 Ski-Doo Formula Plus 503 1987 Ski-Doo Skandic 503 1987 Ski-Doo Stratos 503 1988 Ski-Doo Alpine 503 1988 Ski-Doo Nordik 60 1988 Ski-Doo Formula Plus 503 1988 Ski-Doo Safari 503 1988 Ski-Doo Safari 503 R 1988 Ski-Doo Stratos 503 1989 Ski-Doo Formula Plus 503 1989 Ski-Doo Formula Plus 503 LT 1989 Ski-Doo Nordik 60 1989 Ski-Doo Safari 503 Voyager 1989 Ski-Doo Safari 503 Escapade 1990 Ski-Doo Nordik 60 1990 Ski-Doo Safari 503 Cheyenne 1990 Ski-Doo Alpine II 503 1990 Ski-Doo Formula Plus 503 1990 Ski-Doo Formula Plus 503 LT 1991 Ski-Doo Nordik 60 1991 Ski-Doo Cheyenne 1991 Ski-Doo Alpine II 503 1991 Ski-Doo Formula Plus 503 1991 Ski-Doo Formula Plus 503 E 1991 Ski-Doo Formula Plus 503 XTC E 1991 Ski-Doo Formula Plus 503 XTC 1993 Ski-Doo Alpine II 503 1993 Ski-Doo Skandic 503 R 1993 Ski-Doo Skandic 503 R SLT 1993 Ski-Doo Safari 503 Rally 1994 Ski-Doo Alpine II 503 1994 Ski-Doo Safari 503 Rally E 1994 Ski-Doo Skandic 503 1994 Ski-Doo Skandic 503 R SLT 1995 Ski-Doo Formula 500 SL 1995 Ski-Doo Skandic 500 1995 Ski-Doo Skandic 500 WT fan cooled 1995 Ski-Doo Touring 500 SLE 1995 Ski-Doo Alpine II 503 1996 Ski-Doo Formula SL 500 1996 Ski-Doo Skandic 500 WT fan cooled 1996 Ski-Doo Skandic 500 1996 Ski-Doo Touring 500 SLE 1997 Ski-Doo Formula 500 SL 1997 Ski-Doo Skandic 500 1997 Ski-Doo Skandic 500 WT fan cooled 1997 Ski-Doo Skandic 500 SWT 1997 Ski-Doo Touring 500 SLE 1998 Ski-Doo Formula 500 SL 1998 Ski-Doo Skandic 500 1998 Ski-Doo Skandic 500 SWT 1998 Sk