The Shockwave Clutch with overdrive is currently the best clutch available on the market. This clutch is bolt on performance. The Shockwave line of clutches were designed with consistency and simplicity in mind. They are also built to last. Some of the Shockwave features are: more clamping force for higher torque engines; round main shaft instead of square; wide belt technology; torque is transferred through ball bearings instead of a slide bushing, and much more!