More Details on Spitfire Formula 4 Lock-Ins 101a Natural:
FORMULA 4 - Unbeatable lasting performance SPITFIRE urethane. Fast as hell. Long lasting, abrasion resistance, smooth anti-stick slide with a controllable grip. Guaranteed.
LOCK INS - Asymmetrically shaped wheel designed for more control. A conical cut on one side with a straight edge cut on the opposite built for precise lock in grinds.
101a Durometer
