This is a replacement Losi aluminum clutch shoe & spring set. The aluminum clutch shoe/spring set includes three each precision machined billet aluminum clutch shoes and springs as well as six small shims. The aluminum shoes were developed to withstand the pounding of high horsepower off-road racing for extended periods. Since aluminum is not as sensitive to heat and dirt they offer both superior performance and durability. The included shims are used to space the shoes away from the aluminum flywheel preventing unwanted friction and galling. The serious enthusiast as well as the racer will appreciate the consistent performance and reliability of these hi-tech clutch parts.