80mm Hyper X-360 Wheels (4-PACK) X-360™ - the benchmark for performance cross-training wheels. TheX-360 combines top-end hub technology with a durable, comfortable outdoor urethane compond for fantastic cross-training performance. The choice of top fitness skaters and racers in training. Chemistry: Superior grip, snappy response, ultra resilient compound. Superiour straight line speed with effortless response.