Bedford RLW Brakes

[PDG]

 

 

Attached aresome pictures of my braking system, the vehicle was made in 1970, the circular part of the servo is a secondary brake, possibly emergency, the middle picture shows the fed to the main brake through the chassis, and some pipe ends which are for a piece of kit reputedly removed by the army, however until I plugged the ends there is a third ourt of shot I couuld get no air pressure, can anyone identify the third picture, or give me any information on this system I would be grateful. Paul