The MWC "Depthmaster" Military Diver models are the latest heavy-duty range from MWC, designed to be extremely robust. These watches feature a sapphire crystal and are suitable for diving with mixed gases at extreme depths, thanks to their 100ATM water resistance rating. They also come with a wider 24mm strap (most military diver watches use a 20mm strap) and a non-scratch ceramic bezel that is easier to grip in extreme cold. These watches are specifically built for professional divers operating in challenging conditions.
All MWC 100ATM models are equipped with a helium escape valve. People often ask how helium gets into a dive watch, and the answer is simple: helium molecules are among the smallest molecules, and despite the seals working perfectly to keep water out, helium can still penetrate the watch, whereas other gases and water cannot.
Helium escape valves are primarily used by saturation divers, who spend extended periods at great depths under high pressure. Without the valve, helium molecules can build up inside the watch, causing internal pressure that could damage the watch or even blow out the crystal or crown when unscrewed, which could be dangerous. The helium escape valve automatically releases helium during decompression, preventing this issue. The valve only allows helium to escape and does not let anything external in.
Helium is commonly used in deep-sea diving because it avoids the negative effects of nitrogen, such as nitrogen narcosis. Helium replaces nitrogen in most deep-sea mixed gas diving applications.
In certain situations, divers live in pressurized environments filled with an oxygen-helium mix for days or weeks at a time. When they decompress, the helium must be released to prevent damage to the watch, which could result in injury, such as a blown-out crystal or crown.
Most divers won’t need a helium valve unless they are living in a pressurized environment for extended periods. However, for deep diver watches like the MWC 100ATM range, the helium valve is essential to ensure the watch remains fit for purpose.
This particular variant features a 12-hour European military pattern dial and is finished in black PVD stainless steel. The matte black non-reflective PVD finish is often specified in military contracts, especially for special forces and covert operations. The PVD process chemically alters the steel at a molecular level, making it highly durable, unlike painted finishes that can wear off.
The movement is a high-quality 24-jewel automatic NH35A with a hacking function for synchronization. It also features a 41-hour power reserve.
Dimensions and Specifications:
Movement: 24 Jewel Automatic NH35A with hacking function
Water Resistance: 100ATM / 3,280ft / 1000M
Screwdown Crown
Helium Escape Valve
Width: 47mm with crown (44mm without crown)
Bezel Type: Unidirectional, Non-Reflective, with Ceramic Insert
Thickness: 18mm
Crystal Diameter: 31mm
Crystal Type: Sapphire with Anti-Reflective Coating*
Lug to Lug: 48mm
Weight: 140g
Case: 316L PVD Stainless Steel
Illumination: Luminova on markers, hands, and bezel
Strap: 24mm NATO Webbing Strap
*Many people ask about the benefits of sapphire crystal compared to standard mineral crystal. Synthetic sapphire is much stronger, shatter-resistant, and scratch-resistant. These properties make it highly desirable for military personnel, security forces, police officers, and active outdoor enthusiasts—who account for over 70% of our customers. Over 90% of cracked crystal incidents involve watches with mineral glass. Even hardened mineral crystals do not match the durability of sapphire under extreme conditions. Sapphire crystals are heat-treated to remove internal stresses, making them even stronger, and two layers of anti-reflective coating are applied. Interestingly, sapphire crystal is also used on the latest iPhones. While it comes at a higher price, it is usually found on high-end watches due to its superior durability.
This is the watch used by Adventure filmmaker Tom Smith, which can be seen in some of the images see
