This is probably a good place to dump this, as the G.M. Co name is in the title. Also makes a lot of appearances in the 1//4" socket thread.
After someone ID'd some unknown sockets as being made by G.M. Mfg. Co. of Long Island City, NY, I decided to give them another google, see if more useful information could be found. Right on the edge of useful here, a list of their officers, CEO, etc, but in a 1957 Snippet View

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Will add more info from a different computer in a minute.
Guessing at the words (will work on cross checking later, gotta get back to a bigger problem)
G.M. Co. MFG INC
13-08 43 Ave LIC 1 ST 4-2400
Utility Hardware & Auto Accessories
Pres Trea George S Iskyan
VP K W Russell
VP ** per mgr Leo G Wolfensohn (Wallensohn)
Sec Arthur D Sarkisian (Anthony V sousize)
Ox Mgr Frances DeBato
Controller E J Remce
** T Reilly
Here's a first check "g-m Co Manufacturing" for George
Datamp has the same two patents
US patent D160,605 Combination Bar Utensil was issued to George S. Iskyan of Jackson Heights, NY. It was granted on 10/24/1950.
datamp.org
US patent D172,968 Combination hammer and wrench was issued to George S. Iskyan of Jackson Heights, NY. It was granted on 09/07/1954. Design for a household multi-tool incorporating quick-adjust monkey wrench, hammer, pry.
datamp.org
Here is another few, Not in DATAMP
Not a tool, so not a surprise
Same patentee, but not assigned to G.M. Mfg
Not necessarily a tool, but assigned to G.m. (schrader valve core?)
And finally figuring out the code:
Search and read the full text of patents from around the world with Google Patents, and find prior art in our index of non-patent literature.
patents.google.com
Another version here names appended above)
