I now have four flow meters collecting dust and none of them have threads that can be used in any common application. I assumed that a G3/8 thread was a common 3/8 plumbing thread, turns out no. It's designed for some obscure compression fitting that the local guy at the plumbing store says is only used in dentistry. So after months of waiting for flow meters from China I am left looking for something MUCH more expensive locally. Wish me luck.