Bought this watch whilst serving RAF 1955.no 13589292 brevit2592-1 plaque 80 microns ,still keeps perfect time.
It's really rare to hear of an original owner of this kind of watch. Should be a very nice one, couldn't wait to see better pictures of it.
So assume the owner was 18-20 y/o in 1955, then the watch is ~61 y/o and the owner ~79-81 y/o. The owner got some good and long service of this watch!
Age of watch and myself correct. Only used now on special occasions would like to know approx value unable to get better photo with my camera or tablet.
I'm afraid vague pictures lead to as vague valuations, with those pictures it is impossible to even give a range. The very least needed are better pictures, front and back, ideally with the added information of the watch reference numbers which will be found on the inside of the case back.