This type of brakes is used on Tata vehicles as an auxiliary brake and is meant for use while travelling on a lengthy downhill gradient and in heavy traffic when it becomes necessary to Slow Down continuously over a large distance.

      Figure shows the simplified layout of this type of brake. The main components of this brake are the pressure regulator (common with the service brakes operated by compressed air), foot control valve for actuating the exhaust brake, and an air cylinder wherein the compressed air operates the linkage to actuate the butterfly valve in the exhaust manifold and also the linkage to actuate the control Lever of the Governor.
    
       The brake comes into operation when the foot control valve is pressed and remains engage as long as this valve is kept pressed. The moment the foot is taken off the valve, the break gets released. When the foot control valve is pressed, the compressed air from the air tank enters the air cylinder, where it operates a linkage to close the butterfly valve at the exhaust manifold, which also cuts off the fuel supply through linkage as shown. In this way, this type of brakes effect fuel economy also. This brake is very effective below vehicle speed of 40 km per hour. However, it must be remembered that it cannot stop the vehicle like a service break.