Left.skid control. Right.skid control. A ring with teeth used with a ABS wheel speed Sensor on a vehicle, typically located on a CV axle, rear differential or axle hub. ABS Wheel Speed Sensor. Exc.Japan Built. Japan Built. Exciter Ring. Reluctor Ring. rotor. Skid Control. Wheel Speed Tone Ring. wire. Pump pipe. Included with: Hub & bearing.