If you are installing disc brakes to all four wheels, the use of this master cylinder is mandatory. The stock master cylinder cannot supply the additional pressure

If you are installing disc brakes to all four wheels, the use of this master cylinder is mandatory. The stock master cylinder cannot supply the additional pressure or the correct bias needed in a 4-wheel disc brake application. The answer is our 20.6mm bore Dual Circuit Master Cylinder. We offer one unit for all standard Beetles and another for Super Beetles only. Recommended for all 4-Wheel Disc Brake applications