I wouldn't have a clue.....
I think I had 6 of them hanging on the various tanks of welding gas... they're all different -- and you need different ones for different tasks IMHO..... Like most tools -- you need different ones for getting in to tight places - or one that you can do dirty welding in vs the one you're going to do thin gauge stainless on the work bench... But NUMBER ONE THING YOU NEED TO BE ABLE TO DO IS TO SEE THE PUDDLE. PERIOD.
