Before the introduction of the euro, francs were also used in France, Belgium and Luxembourg, while Andorra and Monaco accepted the French franc as legal tender (Monegasque franc).
Inside the caliper is a brake pad, a small block of friction material backed with a metal plate. When you step on your brake pedal, pistons inside the caliper cause it to apply pressure to the brake pad which squeezes the rotor, causing the car to slow or stop.
Caliper Basics. Brake calipers are simple basic components used to apply pressure and stop the rotor from turning which will reduce the vehicle speed. Brake calipers generally house one or two pistons while others can have up to four depending on the application (heavy duty or performance).