SpudFiles

At the local building supply there is a rack of air tool parts/fittings by
Forney Industries. They make a tank manifold for carry tanks, to fill a flat tire. It works great for pneumatic guns.
It has two 1/4" NPT outlets--one for pressure gauge
--one for quick connect
The high pressure release is built in.
It has a tire valve built in also.
It has a 1/2 NPT male end to attach to tank/gun.
It's approx. 2" in length.
I paid 12.29$ , online they are almost half of that.
CAT.NO. 75550 or 755504
I put one on my first pneumatic, everything on one fitting and two ways to fill.

Cool post a pic so I know what it looks like, the gun that is, I can google the fittin'

I know what you're talkin about. Good idea. I never thought to use one on a gun, though, because carry tanks usually run from 20 to 30 dolllars, respectively.