GM Genuine Parts Brake Backing are designed, engineered, and tested to rigorous standards, and are backed by General Motors. Within the braking system the wheel cylinder is mounted to these brake plates and they serve as the foundation for the brake shoes and other drum brake components. GM Genuine Parts are the true OE parts installed during the production of or validated by General Motors for GM vehicles. Some GM Genuine Parts may have formerly appeared as ACDelco GM Original Equipment (OE).