The Rink Rat Identity Conflict wheel is designed with a professional polymer and Mtech technology that provides extreme grip, faster speed, and an ice-like feel that is ideal for indoor tile surfaces. The hardness of the wheel is a 78a and built with the premium iHub5 that gives optimum balance of weight, strength, and adhesive properties for a lighter weight as well as a higher rating on impact and crush testing.   Pour: Dual Internal Component: Mtech Urethane: Pro Level Grip: 8/10 Speed: 8/10 Wear: 8/10 Hub: iHub5 with Interlock Surface: Indoor Tile Recommended OK for painted, wood or other indoor type surfaces Do not use on concrete or abrasive surfaces