Spitfire is proud to introduce their newest shape to those who keep the underground lit with the Spitfire Wheels F4 101 Tablets 54. Formula Four Performance Urethane lasts longer, withstands more abuse and performs superior to all other wheels. Designed to combine 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, with 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 compound that gives a fast/consistent, smooth slide all the way through. Wheels sold in a set of FOUR.