ROLEX - a gentleman's military issue Oyster Perpetual Submariner bracelet watch. Circa 1977. Reference 5517, serial 5339950. Signed automatic calibre 1520. Black dial with luminous hour markers. Calibrated bezel, stainless steel case fitted to a stainless steel folded link Oyster bracelet with Fliplock clasp. 39mm. Please be aware that this watch has had aftermarket intervention.

When the British Ministry of Defence shifted allegiance for the production of dive watches from Omega back to Rolex in 1971 they requested a number of modifications to the 5513 reference to bring it up to military specifications.

The bezel was to be made from nickel alloy rather than plastic so that it would dent rather than break on impact and the minute markers were carried on all round the bezel rather than for the first 15 minutes as on civilian watches, spring bars were replaced by fixed lugs to take a nylon webbing strap, the 'Mercedes' hands were replaced with larger 'Sword' shaped ones and the luminescent material was replaced with one powered by tritium, a fact signified by the circled T on the dial.

These were tool watches made to be used an abused during active service and so relatively few of the initial 1200 or so have survived. Fewer have survived fully intact as original hands often got replaced by Rolex during service and case backs did not always go back on the right watch during routine MOD maintenance.

The fact that these watches are the last remnants of a very limited production run that was never made available to the public combined with the attraction of an active service history makes these watches highly sought after by collectors.