Timothy wroteWell do know had been around for a long time as I was thinking maybe in or around the 1900 went the first Tubular Cam came out. I believe they was use in and around about 1940 and up….Timothy…..
The Chicago Ace lock was introduced in 1933.*
From Locks and Lockmakers of America, 3rd Edition, Pg. 78 by the late Thomas F. Hennessy, Sr.
Pete Schifferli
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