[Drbraunsr]

Milton V-style (Hi Flo Couplers)
A 'first-world' problem/solution no doubt but these things are slick.
No more ball bearings falling out of the cheapies offered at the big-box stores or the push/pull -- these are direct push and are smooth as 12 year old scotch.

I bought 3/8" for the hvlp guns for the P-car and other assorted air tools.
Life's simple pleasures....