This is an optional Serpent Centax XP Clutch Shoe, and is intended for use with the Serpent 966 and 960 1/8 scale on road cars. This black centrax clutch shoe is made from a redesigned material that gives you more punch during acceleration. Although, due to the nature of the material used on the XP (xtra performance) clutch shoe, you sacrifice longevity, but the extra power gained is worth it.
No adjustments or modifications are necessary for this shoe. It is a direct replacement for the standard brown shoe.