Rolex Submariner 5513 MilSub Watch
Created specifically for the British military, this Rolex Submariner 5513 MilSub Watch is a rare example of purpose-built timekeeping. At a glance, you can see its distinctive sword hands, which — along with the fully gradiated bezel — were added to improve legibility. Fixed lugs replaced the spring bars, improving durability and ensuring the watch wouldn't fall off its now-necessary NATO strap. While these watches were never sold to the public, this particular example is even more rare thanks to its included "Hudson" papers that confirm it was delivered to the British military in ready-for-service condition.