twertsy
Well-known member
If you're referring to the Registered Trademark symbol, that was established in 1946. It's a good postwar tell for WWII collectors in the know on uncertain pieces. I don't know when Plomb started including it in their markings, but that's an interesting side-question. Not 1946, obviously. Not early 50s either, because there's plenty of PROTO without it. Another interesting side-question is when they started marking the detent with the star. All Plomb Empire (PROTO, PENENS, Fleet, etc) drive tool pieces with female openings had it at some point, including extensions. I just think of it as 50s or later, because I don't have too many reasons to be more specific than that. But it might be useful to know when.
I've never seen the "circle R" indicating registered TM on any Plomb or Proto LA marked tool. Advertisements yes, but not on tools.
I'm either going soft, or I was being unduly hard back then. You guys can decide for yourselves! HAHA





