Bighead Shape
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.
Spitfire Duro 99 – The Duro 99 by Spitfire has more speed and control on all surfaces, has flat spot resistance, long-lasting anti-stick slide and a higher rebound compound.