These are typical rubber wheels for small robot mobile platforms. The tire is soft black rubber with light tread for added traction in rugged terrain. An axis adapter is needed which bolts to the back of the hub and mounts to a motor. this adapter can mount to our Micro DC Geared Motor with Back Shaft. These motors are commonly used in our 4WD and 2WD platforms.
You will need our Motor Adapter to fit this into Gear motor.