Backing plate. Left. Rear. Right. A Backing Plates used on a drum brake braking system, used to contain brake shoe dust, as well as protect the brake drum components from water, dirt and debris. A Shield used to contain the brake dust produced by the brake pads of a vehicle's disc brake calipers. This typically is mounted to the vehicle's wheel hub. Additionally, it functions as a splash guard to protect a vehicle's disc brake rotors from water, dirt and debris. Parking Brake. BRAKE. cover. Brake Dust. Brake Splash Guard. Caliper.