Ride the fire through the streets with the Spitfire Formula 4 Radial 101aWheels. Manufactured with the high quality performance, Formula Four urethane. Designed to last longer, withstand more abuse and performs superior over all other wheels. Combined with all the desired properties of a performance wheel without sacrificing any one attribute at the expense of another. Manufactured using a 100% pure urethane compound, Formula Four wheels out-performed and resisted flat spots longer with less wear than all other wheels. Higher rebound for faster speeds over rough and smooth surfaces with a hard durometer for a smoother, faster ride that won't mush out over time. Designed with an exclusive anti-stick compund that gives a fast/consistent, smooth slide all the way through.