A Royal Navy issue Rolex Oyster Perpetual Submariner, circa 1970
The watch has a number of features that distinguish it from the standard civilian Submariner: the case has a matt rather than polished finish; the dial is marked with an encircled ‘T’ to indicate the use of luminescent Tritium on the hands and index; and it comes with gladiator ‘sword’ hands rather than those in the standard ‘Mercedes’ shape.
In addition, the MilSub is fitted with a rugged nylon strap threaded through solid bars that are fixed into the lugs. This method of fitting is safer than a normal strap or bracelet, where there is the danger of losing the watch should one spring bar fail. The nylon, or ‘Nato’, strap also allows the watch to be attached to a divers ‘swimboard’ – a rectangular board fitted with a depth gauge and compass that helps Navy divers accurately navigate underwater.