Carlisle Ultimax 3 has evolved into Ultimax PRO. Thicker cross section so more surface area is in contact with clutch. New cog design dissipates heat and aids flexibility Runs cooler for better performance. Run cool, run long & run fast with Ultimax PROAdditonal Fitment:1998-1999 POLARIS INDY 700 XC1994-1998 POLARIS INDY STORM1997-1999 POLARIS INDY 700 RMK1999-1999 POLARIS INDY 600 XC SP1998-1999 POLARIS INDY 600 XC2000-2000 POLARIS 700 XC1996-1996 POLARIS INDY STORM RMK2000-2002 POLARIS 700 SKS2000-2000 POLARIS 600 XC DELUXE2001-2002 POLARIS 700 CLASSIC1997-1999 POLARIS INDY 700 SKS2000-2000 POLARIS 700 XC SP1998-1999 POLARIS INDY 600 RMK2000-2001 POLARIS 600 RMK1997-1997 POLARIS INDY STORM SE1997-1997 POLARIS INDY STORM RMX2000-2001 POLARIS 700 RMK2000-2000 POLARIS 700 XC DELUXE1999-1999 POLARIS INDY 700 XC SP1995-1995 POLARIS INDY STORM/SKS1994-1996 POLARIS INDY STORM SKS2000-2001 POLARIS 800 RMK