I highly doubt this is a Ref. 2179. The caseback isn't beveled the same way:
Ref 2179:
OP's caseback.
View attachment 212820
Very different. Ref. 2179 should be 34-35mm. This one looks smaller, maybe 32-33mm.
Civilian watch to be sure, but my guess is the 17.8 movement with a spacer as shown above.
gatorcpa
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