I just went and looked at my set-up, which is a portable air tank and a paasche hose. In between the tank and the hose I have a water trap and a regulator, however, when all the smoke clears, you have at the tank end, a 1/4 in female fitting and on the hose end you have a 1/4 in female fitting. The most direct connection would be a short straight nipple that was 1/4 in male on each end. Don't let the look of the paasche fitting bamboozle you, it screws directly onto a standard 1/4 in male fitting (use teflon tape between joints if you wish).
Hope this helps.
Tom