Wiseco 20 x 25 x 21.8mm Top End BearingAs the leading manufacturer of forged two stroke pistons, Wiseco knows top end bearings are crucial to your top end rebuild. Wiseco two stroke top end bearings are manufactured by leading bearing suppliers and inspected for quality. This Part Fits: Year Make Model Submodel 1998 Polaris 440 Base 2001 2003 Polaris 440 Pro X Base 1999 2003 Polaris 500 Base 2000 2003 Polaris 500 Classic Base 2000 2002 Polaris 500 RMK Base 1999 2003 Polaris 500 XC Base