Introduced in 1970 on the Sea-Dweller, our Triplock winding crown, with a triple lock that creates three sealed zones. As early as 1926, our Oyster case came with a screw-down crown to stop water, sweat or dust entering. In 1954, we devised the Twinlock winding crown and its added waterproof barrier to counter any incident that could harm a gasket on a dive. As for our Triplock winding crown, it is a further safeguard in the unlikely event of the crown unscrewing itself 11,000 metres (36,090 ft) down.