Post by scubadiverbob on Feb 28, 2012 10:42:26 GMT -8
You can attach it with the tank full of air. HP air only goes to the outlet if the air is turned on. I like to take my tanks to the dive stores with the spg's attached to get air fills. Sometimes they look at me strange when I tell them they don't have to take off the gauges to fill the tanks ... usually, those doing the fills haven't been into diving very long.
As Bob said, the ports are downstream to the valve, so you can put the SPGs on and take them off with a pressurized tank. IIRC, it uses a 3/8" plug, so either use an old style HP hose, or get one of the HP adapters available.