four.cycle
Well-known member
Private Lugnutz said:Marked simply and only THORSEN 1/4
^ It was later assigned a part number of 33M, but the earliest catalog listing I find for it (in what I have here) is in a 1956 pamphlet - *.pdf format doubtless downloaded from ToolArchives.
In a 1930's catalog snippet, they don't show a 1/4" drive universal joint. Unfortunately there's no date on this one - in the frontispiece it's marked "Catalog 3334", if anything can be made of that.







* I'm a bit puzzled by the notation about "1/4" hex connection", because all of those part numbers on the sockets are the same as the later 1/4" square drive sockets.
* Note that part number 12M is assigned to both the breaker bar and the 3/8" 6-point socket. The 1/4" square drive breaker became an 18M.
* Extension 51M is a mystery. The 1/4" square drive 6-inch extension became a 53M
* "Spintite" handle 15M is a mystery. The 1/4" square drive spinner handle became an 80M
(* It would appear my posting this in the hopes of helping to answer your inquiry just raises more questions.)
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