Both broke within five minutes of use. They are made from the cheapest and thinnest Chinese alloy I have ever seen. One literally fell apart in my hand just as I was about to screw in another fitting. I couldn't believe my eyes - it literally shattered on a razor-thin section of metal casing. Assuming I have two packs, I got a different one. The small pieces of tongue that touch the valve core on the stem broke off when screwed onto the stem. Incredibly bad quality!