A strong, rigorous focus is placed on the waterproofing process throughout the entire production chain. The hermetic properties of each watch are tested in a hyperbaric tank, following an exclusive protocol developed by Rolex, which yields precise and reliable results.

Watches guaranteed waterproof to 50 or 100 metres (165 or 330 feet) are subjected to a water pressure at least equivalent to, or up to 10 per cent higher than that exerted at their rated depth. For divers’ watches, waterproof to 300 metres (1,000 feet) or more, the safety margin is increased to 25 per cent, in strict adherence with the standards in effect for this type of watch.