SMC Male Straight fittings are male NPT on one side, and PTC on the other. SMC fittings feature a metal sleeve which aligns with the inside of the air line, providing an improved seal for 1/4, 3/8 and 1/2 PTC options. SMC fittings are DOT approved for 1/4, 3/8 and 1/2 inch PTC options.
Most of them leaked. Seem to be cheap fittings. Ended up swapping them out for compression union found else where and now I have no leaks
Reply:
Thank you for taking the time to leave some feedback. I am sorry to hear that you had some issues with the fittings. We sell a lot of these and have not had any issues with them at all. I can say that the hose needs to be cut perfectly straight and pushed all the way into the fitting. Otherwise, you will have leaks if the hose has imperfections in the cut. If you ever have any questions or concerns with purchases we are always happy to help get the issue resolved!
Bought a handful of these to replace previously purchased SMC fittings that started to leak. Ordered extra just Incase, one started leaking after a few days...but no big deal, that was expected. A few months later and the others have developed slow leaks between the black collar and the brass body of the fitting. (Not from between the air line and the black collar) All lines were cut fresh and square when new fittings were installed. Will definitely be phasing my SMC fittings out in favor of the nickel plated brass fittings that haven't given any issues in over 3 years, once I can figure out which brand they are.