Since the valve stems don't have a brand name anywhere on them I am concerned I may get the wrong size or thread type. Are plumbing parts consistent all across the board? I just can't seem to get this drip to stop completely. I can slow it down, but the washer ends up getting wrecked in about 3 weeks or a month and here we go tightening it closed harder and harder and eventually replacing it (again). The valve seats look o.k. and it wouldn't cost much to replace, but again, if I get the wrong size or thread type and then screw up the female thread it would take lots of money to fix that. Any advice out there on how standard these items are as far as sizes/threads are concerned?