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.

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

Conical Full Shape – With a wide riding surface and a cutaway design, this shape has unmatched control and lasting speed everywhere.

Smooth Surface – Smooth wheels have less surface friction than treaded wheels and are easier to slide.

Wide – More traction and stability at high speed so you'll be less likely to slip out of your line.