A brush conducts currents between wires and a rotating shaft, found in an electric motor. These are found in "brushed" power tools, corded and cordless. In brushed power tools, an electromagnetic current is created by the current traveling from the power source through the brush to the commutator which sends it to the armature (made of bundles of copper wiring) and an electromagnetic current is made, causing the motor shaft to continuously rotate until the electromagnetic field stops. Find the brush for your brushed tool here! We carry a wide variety of sizes!