4992B Case-Back Markings

I just picked up a Hamilton 4992B with U.S. Govt. stamped on the movement. The back of the case contains the following:

Watch
Navigation Master
MS 28076
Mfr's 33106
DA-36-038-ORD-21409-M
Serial No 23421
Hamilton Watch Co
U.S.N.

These are not the standard markings that I have seen on a 4992B case. I did a search and found the National Maritime Museum website has a 4992B listed with a description of identical case markings (SN is different).

Does anyone have any information on the origin of these case markings?

Thanks,
-Steve

Posts: 266 | Location: Dover, New Hampshire U.S.A. | Registered: February 14, 2005

Terry Hill

posted

From documentation I have seen, this case inscription was part of the contract description.

The contract spelled out the beginning serial number for the case marking and other info.

Posts: 1496 | Registered: November 20, 2002

Ignored post by Terry Hill posted

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Lindell V. Riddle

IHC President
Life Member

posted

Great link Steven,

Here are the other "4992B" listings in this forum...

Click to access all "4992B" through "Find-Or-Search" in Military Timepiece Discussions

I've noticed the earliest examples show the "Manufacturer's Part Number" as "4992B" on the case-back. Then later on "33106" replaces the 4992B grade number and 33106 becomes their part number.

These are great watches, there is a lot to discover in collecting and researching them.