The Derby Worx name says it all! These SUPER "H" SPEED WHEELS 530 are the absolute best H wheels on the market. Each set of wheels is made using parts which came form an Official BSA® Grand Prix kit. Each wheel is lathed to perfection using a CNC lathe. The center is under cut, leaving small raised edges on the outside rims of the wheel. These edges are the only part of the wheel that actually touches the track. Wheel/Track contact is reduced by over 90%. For pinewood derby racers who need to take it to the next level of performance.