Strong Parameters: Shaft size: 5/8 ", Keyway : 3/16", Forward ratio: 1: 1.3, Reverse ratio: 1: 2.6, RPM: 2300. High Adaptability: This go-kart transmission kit is suitable for # 35 chain 12T or # 40/41/420 chain 10T kart, Dune Buggies, UTV, and other off-road vehicles. Perfectly Fit for 2-7HP. Easy to Install: This go-kart forward reverse gearbox is easy to install, suitable for people who like DIY assembly of karts, just follow the operation to complete the installation and use. Quality Material: This go-kart gearbox is made of high-quality metal, which is light and sturdy; it allows the operator to choose three positions: forward, reverse and neutral. Complete Accessories: This go-kart reverse gearbox includes 1 x gearbox with 3/16" keyway, 1 x gear lever assembly, 1 x gearshift disc, 2 x transmission lines, 2 x sprocket wheels, and 2 x mounting plates.