Just received this item and had to try it. The cartridge must sit directly on the valve stem, otherwise it will leak. I had to press the liner onto a hoop to prevent air escaping when inflating, which somewhat defeats the purpose of the self-locking liner. The gauge is nice and easy to read, it's a lot bigger than I imagined but feels solid. I had to use a lot of teflon tape on the air fitting I installed to connect it to my compressor hose. I like the look of the stainless steel tubing, butβ¦