US Navy Waltham quartz chronometer Cir. 1991

[River Rat 1]

I am looking for info on this Waltham quartz chronometer issued around 1991 to the US Navy. The Navy use to use a Hamilton model 21 chronometer since WW2 till the 1980's in the 1990's they switch for a short time with quartz with Waltham and another made by Marathon. Only seen two other Waltham's my serial number 1313 the other two another collector has 1679 and another for sell on the net 1690. There is some info from Whittney's book military timepieces with a little info when Waltham was designing it but as you see it turned out different. The dial set up and case design different. Another collector thought it would slide in a slot on the chart table due to the two nobs on the front that you would hold he might be right. Anyone ever see one on ship? Don't think the Navy uses them anymore since GPS. Any info would be appreciated.

[River Rat 1]

Here it is next to the Hamilton model 21 it replaced.