The Pro Body Tool is a precision CNC machined sizing pin made from C.R. steel with zinc plating for corrosion protection. Ensuring proper axle fit by reaming undersized wheel bores (great for wheels that don't fit on the mandrel!). Ensures accurate rotation by squaring the inner wheel hub to the wheel bore for proper mounting on a Wheel Mandrel. Reduces the wheel hub to a car body braking effect by accurately and easily coning the inside wheel hub.