This is a Hamilton G-974 Special U.S.A.A.C. Type A-9, Navigation Master Watch, possibly a prototype. It has a side hacking mechanism.

Caseback...

Picture of the side hacking lever.

James, very nice. I don't think I have seen this model with a stop/hack feature before.
Regards,
Ernie

JAMES
Interesting watch thanks for posting it.

I'm impressed. You have some rare and interesting watches. Could we see an image of the movement?

Best regards,
Greg

Thanks everyone. Unfortunately, I don't have apicture of the movement with and the watch is back at my home in Texas. I'll try and get a good picture of it when I'm back next time. I am only speculating when I say it might be a possible prototype. The TIME LABORATORY stamping suggests (to me anyway) that it was made for and used in some sort of a test or maybe as a prototype of some sort. I find it strange that the MFG ASSY DWR No. is 0. Also, the SPEC. No. starts out with and X-27783. I've never seen another like it before but have seen a Longines with this type of side hacking lever.

James, I seem to recall that for other types of equipment, a contract number starting with an X indicated experimental items.

Thanks for this and your other fine posts.

Best regards,
Greg