MODEL RELEASED. Formula One car preparation. Mechanic changing the brake settings at the front of a racing car. The front end cone has been removed, revealing the brake master cylinders (centre). These contain brake fluid for the hydraulic brake system. Formula One cars have a twin-circuit braking system with two separate reservoirs for the front and rear wheels. This ensures that, in the event of a failure in one circuit, braking will still be available through the other circuit.