When the car is going to be raised for a long period, the Gate Valve can be closed after lifting the car (and after placing safety stands under the car) to prevent small leaks from draining your air tank.
This valve should be installed between the Inlet Receiver and the hose (leading to the jacks) in an air jack system. 3/8 NPT female threads accept the old-style Inlet Receiver (Part No. 1860-106, no longer available). 6AN male threads on the outlet accept a standard 6AN hose end (sold separately). Inlcudes a jam nut for bulkhead mounting.
In the heat of battle, the receiver assembly can be hit fairly hard with the wand. You may need to fabricate a support bracket for the receiver if the body of the car is not strong enough to take the abuse.