Chrome-plated device, air-operated, suitable for bleeding the hydraulic brakes and clutches of all motor vehicles. The bleeding operation can be carried out in just a few minutes by one person. The brake-bleeding device is equipped with an elastic inner membrane which hermetically separates the fluid contained in the top chamber from the air contained in an underlying chamber, thus preventing any risk of emulsion. Furthermore, it is equipped with a third high-pressure reserve air chamber (8-10 bar controlled by the bottom air regulator) enabling several bleeding operations to be carried out at a constant pressure and without requiring additional recharges. Also suitable for bleeding systems with braking control and ABS (max. at 1 bar).