Tattoo Wheels are your best companion for attaining maximum speed, longer roll and of course a smooth ride. Featuring a unique urethane formula, Tattoo Wheels are designed to go faster with no flat spots. CONICAL INSIDE EDGE FOR BETTER LOCK-INS DOUBLE THE RESISTANCE TO FLATSPORTS Diameter: 54mDurometer: 100a* ALL TERRAIN* SMOOTHER RIDER* NO FLAT SPOTS* CONICAL SHAPE