4mm bearings: the size of other devices 4 * 13 * 5mm, motor class, suitable for motor model.
5mm Bearing: size 5 * 14 * 5mm, motor class, suitable for motor model.
6mm Bearings: size 6 * 17 * 6mm, motor class, suitable for motor model.
8mm Bearings: size 8 * 22 * 7mm, the motor class, suitable for motor model.
10mm Bearings: size 10 * 26 * 8mm, the motor class, suitable for motor model