Bearing Wheel Rear T12-000Rear Wheel Bearing Upgrade KitBearings incorporate larger balls providing larger load carrying capacity, and now sit on the axle instead of the wheel collars Collars and bearing spacer made of military hard anodizing to prevent wear Collars incorporate Pivot Works watertight O ring design to keep hubs dry Upgrade kit includes: Bearings Seals Watertight wheel collars Bearing spacer Two sets of O rings Replacement bearings and seals sold separately.