Spitfire OG Classics in 54MM feature a wider riding surface and cutaway shape for control and slide versatility. Built with Spitfire’s trusted Formula Four urethane in 99DU for unmatched flatspot resistance, speed, and durability — designed to perform at any level, in any terrain. Diameter: 54mm. Width: 32.3mm. Riding surface: 22.2mm. Set of four.