Tradition of leadership

The screw-down winding crown and the case with screw-down back together make up the famous Oyster. This exceptional waterproof design was patented in 1926 and gave Rolex watches their reputation.

It was the beginning of the Rolex success story. The crown not only hermetically seals the case – it also provides access to the watch's key functions. The Twinlock system, introduced in 1953, guarantees that the screw-down winding crown is perfectly water-resistant thanks to two sealed zones. Also, The Triplock system, introduced in 1970, has a third sealed zone inside the tube of the crown. It was designed to offer increased water-resistance for the Submariner, Sea-Dweller and Rolex Deepsea divers' watches, guaranteed waterproof to depths of 300 metres, 1,220 metres and 3,900 metres.