US Postal Service, Reg'd Mail counter padlock lock, RPO

Here is an early version of the Registered Mail Lock that includes an internal counter that records the number of times that the lock has been opened:

This obsolete US Mail Registered Mail padlock with counter reads ''U. [star] S." / REG'D / MAIL.'' On the back it reads: ''T 1218.'' The counter is currently at 0127 ''in the window,'' meaning it has been opened only 127 times during the past 120 years. This lock includes an excellent, reproduction working key and is in very good condition. This is a very nice, unusual and uncommon lock and would make the great gift for that avid ''Lock and Key Collectors'' collection, formerly owned by James R. Mundy, a noted historian on postal locks. As you’ll observe in both illustrations, all features of the lock are clear and distinct.

This padlock has a cast brass case, with the shackle collar and rotating shackle made of architectural bronze. It is circa 1880s but continued in usage through the 1920s, being repaired when necessary. The obsolete flat-style key was assigned to the Treasury Department. Although registered mail shipments passed through the postal system with this lock, Post Office Department employees could not open those pouches with their standard-issue keys. Only U.S. Treasury personnel were assigned keys to unlock shipments of currency and coin. - eBay

This lock appears to be in great condition and even more importantly comes with a key. Oddly enough, the key looks the same as for the newer version of the Registered Mail Lock, but I am unable to tell for sure until I try one myself.

This lock sold for $386.06 (Plus $3.95 Shipping).

A second lock and key from the same seller went for $381.06 (Plus $3.95 Shipping). (Auction listing here)

To compare, a similar lock was auctioned off earlier the same day:

Reg'd U.S. Postal Service Mail Lock w/counter--Obsolete

This is an Obsolete US Mail Reg'd Pad Lock w/counter. On the Front of the lock it reads: REG'D U.S. MAIL, and on the Back it reads: R.M.S. 2830 The counter is currently at 0484 and is in good condition. It is locked at this time and does NOT come with a key. This is a very nice, unusual and uncommon lock and would make the great gift for that avid "Lock and Key Collectors" Collection. Please See Pictures. - eBay

This lock sold for $385 (Plus $3.95 Shipping). This lock has no key.
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