Vacuum boosters are located between the brake pedal and master cylinder. It makes use of the difference between atmospheric pressure and the vacuum generated by engine at in-take manifold to magnify the force exerted on foot pedal.

A booster is composed of a main body, a piston, piston return spring, reaction mechanism and control valve mechanism.

Local OEM vacuum boosters are produced by San Yes with Continental Auto System of Germany under a technical cooperation agreement. With development of matching brake system components, San Yes is able to achieve highest safety requirements.