Durable - Our AlveyTech 10 tooth chain sprocket is built to withstand high torque and provide a smooth power transmission to your vehicles drive system Compatibility - This sprocket is designed for any go kart that uses a series 20/30 torque converter. It uses the common 5/8" bore (inside) diameter that matches up to the 5/8" axle shafts on many go kart models Specifications - Our sprocket features a Milled 3/16" keyway slot and is a type C sprocket designed for #40, #41, and 420 chain sizes. 5/8" inner bore diameter and 1-3/4" external sprocket diameter Sprocket Type - This is a Type C sprocket where the 5/8" hub is centered equally on both sides. (Type B sprockets have the hub offset to one side.) In addition, this sprocket is milled for a 3/16" shaft key Description: Tooth count: 10 Bore diameter: 5/8" Outside diameter: 1-3/4" Hub width: 5/8" Milled keyway slot: 7/32" This 10 tooth chain sprocket is used with size #40, #41, and 420 chain found on 20 & 30 Series torque converters. It uses the common 5/8" bore (inside) diameter that matches up to the 5/8" axle shafts on many popular models. This is a Type C sprocket where the 5/8" thick hub is centered equally on both sides. (Type B sprockets have the hub offset to one side.) In addition, this sprocket is milled for a 7/32" shaft key.