Krypto Route Outdoor Quad Roller Skate Wheels by Kryptonics - Your Choice of Wheels Colors & Sizes! - Made by Kryptonics USA, this skate wheel is designed for outdoor use. The high-rebound 78A formula urethane is durable and absorbs road vibration. A contoured & convex profile has made this wheel the skaters choice for over 25 years. 40mm wide.