robzilla
+1y
I bagged my civic 6 years ago, I used 1/2" airline (DOT NYLON air brake line). The pressure I'm filling my tank to is 145PSI. I originally used the press in connectors. The press in connectors all started leaking 2 years later. I switched to DOT brass air brake fittings. They have a ferrule that crimps the line also the fitting has a brass insert that goes inside the airline making a snug fit and supports the nylon airline from the inside.
A compression fitting is setup the same way without the brass insert, so I would not use it for Nylon air line.
Maybe other guys have had problems with them but these fittings have worked well for me without leaks.