Genuine OEM Volkswagen Vented Brake Disc, part number 1J0615301M. This vented brake disc rotates with the wheel and is gripped by the brake pads to slow down the vehicle, with internal vanes for cooling. It is located at position 11 in the diagram. Genuine OEM brake discs are manufactured with precise metallurgy and balancing for optimal heat dissipation, consistent braking, and long service life.