Dynamic Balance Performance: The drive clutch axle is processed for dynamic balance, lowering wear-related imbalances and ensuring smooth operation with minimal noise and vibrations. Durable Alloy Construction: Crafted from iron and aluminum alloy, the primary driving clutch replacement boasts a sturdy build with excellent heat dissipation features. Three Shifting Modes: Equipped with a handle, this gearbox offers three easy-to-use shifting modes: Forward, Reverse, and Neutral, allowing for convenient and straightforward operation. Adaptation Parameter: This drive clutch adapts to vehicles. Shaft size: 5/8 ", Keyway : 3/16", Forward ratio: 1: 1.3, Reverse ratio: 1: 2.6, RPM: 2300. Fit for engines 2-7 HP: This 30 Series forward/reverse gearbox kit is designed for go-karts, dune buggies, UTVs, and other off-road vehicles with #35 chain 12T or #40/41/420 chain 10T.