Elgin Factory Crown for Military Issue Elgin 8/0s Grade 539 Wrist Watch No. EL-285-2104S

Elgin Factory Crown for 8/0s Grade 539 Elgin Military Wrist watch, issue spare part #FO36-7198103, originally packaged in March 1951, new in replacement packaging. The TM9-1575 Ordinance Maintenance Manual confirms this was made for the Model 1783 Grade 539 movement in the case with the screw-on back, which was either 7j or 15j. That said, as near as I can tell these came in a couple of different tap sizes and perhaps even other slight variations (Elgin P/N's EL-285-2104S and EL-285-2104K), with this being the "S" and measuring as a T10. I specialize is hard to find watch parts so I usually have whatever you might need, all watch parts are unconditionally guaranteed and reasonable offers are always welcome. Images do a suitable job of representing the item.