Conical Full Shape - Wider version of the conical shape, wide riding surface, cut in sidewalls to decrease weight. Solid, controllable shape for all terrains.

99a Durometer–More speed and control on all surfaces. Unmatched flatspot resistance. Smooth, anti-stick ride. High-rebound compound.

Formula Four Urethane–Formula Four urethane is unlike any other. Both in the streets and under high-speed stress tests in Spitfire's lab, Formula Four wheels retained more material, coned less and kept their original shapes and sizes longer than any other wheel.

High Rebound Compound