Reg'd US Mail Lock - Innards

Here is an interesting photo of a Registered Mail Lock that has been opened to expose the enclosed counter mechanism.

This is an antique U.S. Mail lock that was in the box that was sealed in 1939 and appears to have been taken apart to understand the working parts of the lock. - eBay

this item went for the opening bid of $24.99 (Plus $6 shipping).

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