Ok, this might be a dumb question, but I have a "Nylon Hose Barb" A-269 3/8"x 1/2" MIP (The outside of the threading looks like 7/8" ). I want to put a low profile, preferably plastic, nylon or pvc type of Nut on the threads, to tighten it down against a surface, and being a newbie, don't know what size of nut to look for, or even where to find one. I was looking 1/2" but they look too small (online) and thinking I should be looking for a 7/8" part? So question 1, what size specification should I be looking for? I would consider a less-corrosive metal part as well, if that's the only option. The application for this is a make-shift basin drain, thus the need for a low profile nut ( I may also cut the un-needed threads.) I also want to put a washer on the bottom of the nut to prevent leaks between it and the bottom of the basin. Note, I'm willing to take another part like a coupler or cap and cut it to give me my part, if not readily available. So question #2, what part should I be looking for? Any help is greatly appreciated, thanks!