Serpent S400 Front One way axle
New for the S400, Serpent has introduced the long awaited front one-way axle set. Sold complete with everything needed, including the 35T composite pulley, when installed the set gives the car more steering and is perfect for use on carpet tracks, especially with foam tires. To improve durability the drive adaptors have been made from steel, yet remain lightweight due to their hollow design.
Source: Serpent [serpent.com]