Diameter of wheel: 75mm (7.5cm), kit contains: Single shaft bo motor with wheel x 2. High quality wheels for coupling with bo-1, bo-2 type of dc motors. This wheel can be coupled to bo type motors using a small screw (screw not included).
DC motor with gear box which gives good torque and rpm at lower voltages. This dc motor can run at approximately 200rpm when driven by a Dual Li-Ion cell battery at 6 V and approximately 300 rpm when connected to 9V. It is most suitable DC motor for light weight robot running on small voltage.