K2 Booster Inline Skate Wheels and Bearings . The Booster Series make up K2's recreational wheels. The urethane provides good durability and comes in a bullet profile that is focused on comfort and control. The price is for an 8-pack of wheels, conveniently pre-assembled with great quality TwinCam ILQ Bearings (ILQ5 or ILQ7 depending on wheel size) and 6mm bearing spacers (add Sonic Floating Spacers for 8mm Axles).

The 72-76mm wheels have an 80A hardness for grip and control, with the larger 80-84mm wheels coming in 82A hardness for added speed and durability.  Designed for outdoor skating, but they can be used indoors at the rink l depending on the skater's weight and surface.  All come with a multi-purpose storage bag.