Description Set of 2 6302ZZ double shielded scooter wheel bearings. Also commonly referred to as 6302Z series. Shielded (ZZ or Z suffix) scooter bearings of this size are commonly used in wheels, transmissions, gearboxes, and various other GY6/QMB139 engine components. These single-row, deep groove ball bearings are designated as medium-weight and feature a 15 mm diameter bore hole. Be sure to check your existing bearings for the series number, which is often etched onto the outside wall of the bearing. Specifications Diameter (Outer): 42 mm Diameter (Inner): 15 mm Width: 13 mm