This differential kit comes with an upgraded pinion bearing. This bearing and seal kit works on the following models
1998 - 2000 Arctic Cat 400 4X4
1998 - 2000 Arctic Cat 400 2X4
1996 - 1998 Arctic Cat 454 4X4
1996 - 1998 Arctic Cat 454 2X4
1998 - 2000 Arctic Cat 500 4X4