I bought a 1/2" water filter to use in the softwash system I am assembling. The inlet and outlet are NPSM. Not NPT. NPSM is a straight thread, not tapered. I thought piping was either NPT or if not tapered it's sealed with a gasket or O-ring. This is just a female threaded opening with no way to deal with an O-ring.
So how does NPSM seal if not tapered or an O-ring?
So how does NPSM seal if not tapered or an O-ring?