They are air operated, graduating control valves of high capacity and fast response
Upon signal pressure from the service brake valve, they graduate, hold or release air pressure from the chambers to which they are connected
Relay valves are available in both remote and reservoir mount designs and feature inlet/exhaust valve cartridge replacement without line removal
The R-8 relay valve incorporates an integral double check valve with a balance port connection which provides both an anti-compounding or quick exhaust feature depending upon vehicle application
The anti-compound feature is used when these valves are used to control spring actuated parking features
