All divers’ watches share certain characteristics that make them divers’ watches: unidirectional rotating bezels, secure screw-down crowns, higher-than-typical water resistance. Some of these divers’ watches, however, go the extra mile (or fathom), with cases that can descend to 3,000 or even 4,000 meters, chronographs operable at incredible depths, or high-tech depth gauge devices built into their mechanical movements. Below, we take a look at seven of these “extreme” dive watches and what sets them apart from the pack.

The Rolex Replica Sea-Dweller Deepsea has a water-resistance level of 3,900 meters (nearly 13,000 feet), and it is more than 10 percent slimmer than it otherwise would have been thanks to a special case construction developed by Rolex. It consists of three pressure-absorbing elements: a 5.5 mm thick sapphire crystal, a 3.28-mm-thick caseback made of grade 5 titanium, and an inner ring (on which both of them rest) made of Biodur-108 steel. Last summer, Rolex launched the new Rolex Deepsea D-Blue Edition (pictured below), with a proprietary “D-Blue” dial that is dark blue at the top, and then darkens gradually to black at the bottom.

Rolex Sea-Dweller Deepsea D-Blue Edition

The Breitling Superocean Chronograph M2000 has a chronograph that can be operated at a depth of 2,000 meters underwater. The watch is the first to feature a patented magnetic push-piece system, in which the chronograph controls are operated via the metal of the case. Along with the screw-locked crown and the 4-mm-thick sapphire crystal, these pushers enable the wearer to use the watch at the extreme depth of 2,000 meters (or 6,600 feet) without the risk of water seeping in.

Breitling Superocean Chronograph M2000

The Ball Engineer Hydrocarbon DeepQUEST has a water-resistance of 3,000 meters, achieved by crafting the entire case out of a single block onto which the bezel is directly screwed. The crown seals, generally considered the weak point of a watch in terms of water resistance, have been strengthened to prevent entry of water when in the screwed-in position. The Rolex Replica Submariner Watches also has a nonreflective sapphire crystal with its thickness raised to 5.3 mm and an automatic helium-release valve.

Ball Engineer Hydrocarbon DeepQUEST

The Deep Blue Depthmaster 3000M, as its name suggests, is water-resistant to 3,000 meters. The Rolex Replica Yachtmaster watches is powered by the Japanese Miyota 9015 automatic movement. The 49-mm stainless steel case features a helium valve with a protective cap. The sapphire bezel is filled with Super-LumiNova and the domed sapphire crystal is 6 mm thick.

Deep Blue Depthmaster 3000M