Supply device for braking system, in particular for vehicle and method for mounting such system

The device has a supply tank (2) of a master cylinder and a rigid fixation support (4) for the tank (2). The tank (2) and the fixation support (4) has male portions (26) and female portions (28) i.e. orifices cooperating together. An elastic unit (30) is interposed between the male portions (26) and female portions (28). The male portions are formed by three pins projecting from a lower wall of the tank. An independent claim is also included for a method of mounting a fuel supply system.