A rare vintage Rolex watch found at the bottom of a dusty old box has sold at auction for over 200,000 British pounds ($272,100).

The 1954 Rolex Submariner 6200, believed to be one of only 300 ever produced, was discovered by the seller in a box of forgotten possessions passed down to her as inheritance upon the death of her uncle, according to a press release. Thought to be worthless until the Rolex name was spotted on the dial, the anonymous new owner took the item to a local jeweler who advised her on the rarity of the wristwatch.

Listed through Watch Collecting, a specialist selling platform devoted to prestige and luxury watches, the Rolex “went on to break records with a winning final bid of £205,500, making it the most expensive timepiece ever sold on the website,” according to the release.

The Submariner 6200 features the A296 automatic movement with both gilt dial and gilt Mercedes hands finished in original radium luminous material. The thick case and prominent 8 millimeter “Big Crown” allow a deeper depth rating of 200 meters – subtle hallmarks of a professional tool diving watch.

Adrian Hailwood, head of Watch Collecting, said: “We are delighted to be part of the history of this magnificent 1954 Rolex Submariner. The condition is everything a collector could hope for with original components, unrestored condition, and featuring all the authentic signs of wear of a 67-year-old legendary Rolex.”