Product Details

SKU: 100ATM/12/SS/AUT

The MWC Depthmaster is part of our latest generation of heavy-duty military divers’ watches. Built for professionals operating in extreme environments, this model is engineered to perform under the most challenging conditions.

With an impressive 100ATM (1,000m/3,280ft) water resistance, the Depthmaster is suitable for mixed gas diving and extreme depths. It features a scratch-resistant sapphire crystal, a non-reflective ceramic bezel for improved grip in cold environments, and a 24mm strap width—wider than the typical 20mm seen on most military divers’ watches.

Built for Professionals – Helium Escape Valve

All MWC 100ATM models include a helium escape valve, a feature essential for saturation diving. Helium molecules are extremely small—so small, in fact, that they can pass through the seals of a watch during prolonged exposure in pressurized environments, even when water and other gases cannot.

In saturation diving, helium builds up inside the watch case. When decompressing, this trapped gas can create dangerous pressure, potentially blowing off the crystal or unscrewing the crown, which could seriously damage the watch or even injure the wearer. The helium escape valve prevents this by automatically releasing the gas during decompression—while still blocking external elements from getting in.

Even if most divers don’t need this feature day-to-day, in watches designed for extreme-depth operations, it’s absolutely essential for safety and functionality.

Why Helium in the First Place?

Deep-sea divers often use a helium-oxygen gas mix to avoid the negative effects of nitrogen, such as nitrogen narcosis. In these situations, divers may live in dry pressurized habitats for days or even weeks at a time. As they surface and decompress, the helium must escape from both the diver and their equipment—including their watch.

If this gas isn’t safely vented, the pressure can destroy the watch—or worse, injure the diver. That's why the helium escape valve is standard across our 100ATM range.

This Variant – Automatic Movement & NATO Dial

This particular version features a European NATO-style dial, a brushed 316L stainless steel case, and a high-grade 24-jewel NH35A automatic movement with hacking function for precise synchronization. It also boasts a 41-hour power reserve, making it ideal for extended operations.

Specifications

• Movement: 24-Jewel Automatic NH35A with Hacking Function

• Power Reserve: 41 Hours

• Water Resistance: 100ATM / 1,000m / 3,280ft

• Crown: Screw-Down

• Helium Escape Valve: Yes

• Case Diameter: 47mm (including crown), 44mm (excluding crown)

• Bezel: Unidirectional, Ceramic Insert, Non-Reflective

• Case Thickness: 18mm

• Crystal: Sapphire with Anti-Reflective Coating

• Crystal Diameter: 31mm

• Lug to Lug: 48mm

• Weight: 140g

• Case Material: 316L Stainless Steel

• Illumination: Luminova on Hands, Markers, and Bezel

• Strap: 24mm NATO Webbing (1 x Black, 1 x Grey)

Why Sapphire Crystal?

Customers often ask: Why choose sapphire crystal over mineral glass? The answer is simple: durability and clarity.

Synthetic sapphire is exceptionally hard, making it both scratch- and shatter-resistant—key for military personnel, law enforcement, and anyone with an active lifestyle. Over 70% of our customers fall into these categories.

To put it in context: in over 90% of cracked crystal incidents we see, the watches had mineral glass—even the hardened type. Sapphire offers superior protection and longevity. It's heat-treated to eliminate internal stress, then coated with dual anti-reflective layers for visibility in all conditions.

You’ll even find sapphire in the latest iPhones—it's a mark of quality, and one of the key features that sets this watch apart in the field.

• Delivery

  • Delivery charges are as follows:

    USA/CANADA	EUROPE	UK	REST OF THE WORLD
    Tracked Mail US$11.50	Tracked Mail €11.75 / £10.25 / US$11.50	Tracked Mail  £9.95	Tracked Mail US$11.50 / €11.75 / £10.25
    Express Courier UPS or FedEx  US$25.00	Express Courier UPS or FedEx  €27.50 / £24.00 / US$27.00	Express Courier  UPS £12.95	Express Courier UPS or FedEx  US$41.50 / €42.50 / £36.50

    You will generally receive two emails after placing an order, the first will be a confirmation of receipt of the order and payment, this will be followed by a notification of shipment  once the goods are dispatched. When an order and payment has been processed, goods will be shipped by the Post Office or Courier within 48 hours. Please note that our shipping centers are closed on Saturdays and Sundays therefore orders placed during this time may take up to 72 hours to be dispatched, this includes orders after 13:00 European time on Fridays.

    The estimated delivery times in working days are set out below: *

    • USA Registered Mail: 4 to 12 days
    • USA UPS: 2 to 3 days
    • Europe UPS: 2 to 5 days
    • Europe Registered Mail: 7 to 14 days
    • UK DPD or UPS: 12 to 48 hours
    • UK Royal Mail: 1 to 3 days
    • Rest of World UPS: 3 to 10 days
    • Rest of World Registered Mail: 7 to 21 days

    All shipping estimates exclude Saturdays and Sundays when our packing and shipping centres are closed and also some countries postal services do not operate at the weekend.
    

    * Some countries are prone to be notoriously slow to process goods on arrival, among these countries are Israel, Hong Kong, Macau, Mexico, South Africa and some South American countries. We also tend to experience significant delays with many countries in Africa in addition to South Africa, you can always contact us for advice although we do not know with certainty exactly which countries will be slow, and which will be fast but the above estimates are a pretty good guide for most countries, keen in mind remote territories or those with slow customs processing can also tend to be problematic. Regardless of the processing speed, all of our shipments are fully insured against Loss.

    Please Note: We recommend using UPS, DHL or Fedex, which we offer as an option, if the delivery is very time sensitive and you are aware that your local Postal Service he's not particularly reliable.

    Whilst we make every effort to deliver your order within the above timeframes this is a guide and delivery cannot be guaranteed. We will not accept responsibility for delays caused by our Couriers or any National postal service. If the goods are not delivered within the time we have estimated, please feel free to contact us or email admin@mwc.watch, and we will do everything possible to resolve the issue promptly. We will not be liable for any loss caused to you by late delivery.

    Our delivery charges covers the cost of shipping the goods to you. However, this does not include import charges and administration fees to clear the goods when entering your country. 

    If you need to clarify any details regarding local taxes for your location, please contact us before placing an order. For clarification, goods shipped to the EU can be dispatched from our EU location if ordered on this site, and we also have a UK shipping center if you order at www.mwcwatches.co.uk

    In the United States, orders under $800 do not incur taxes or fees. In Australia, orders up to AU$1000 are tax-free. Many other countries have similar regulations, which you can verify using this helpful link: Zonos De Minimis Values and also another link below to calculate taxes for shipments to most countries which is here https://www.simplyduty.com/import-calculator/

    It is the responsibility of the purchaser to understand that charges may apply and pay all subsequent import tax and duty on goods shipped to their respective Country. In the instance that items are returned to MWC as a result of a rejected payment, subsequent charges incurred such as Import Duty and processing costs will be deducted from any refund issued. For further information on this please contact accounts@mwc-distribution.com 

    We do not accept any liability for goods that have been lost after delivery to a PO Box. We reserve the right to cancel orders where the delivery address is a PO Box. Furthermore, we also do not accept any liability for goods that have been lost after they are confirmed as delivered to APO or BFPO locations. 

    It is the Customer's responsibility to notify us if the goods have not been received within 21 days of the estimated delivery date or time of ordering. If no notification is made within this time period the buyer shall be deemed to have received the goods.

    Failed delivery of an item ordered due to non-acceptance of the delivery

    Please note that if you order an item and the delivery company inform us that the item was refused it would be returned back to us, in many cases especially with FedEx, UPS etc they will also charge a return fee to send it back. Because in these circumstances we have done everything that is required to get the item to you we would refund less both the outbound and Inbound shipping charges once the item was received back at our packing and shipping centre. Unfortunately sometimes if you are having the order delivered to a business location the people receiving inbound parcels are prone to refuse an item without checking with the individual concerned we would strongly recommend being very cautious in this situation and notifying the people who handle the incoming parcels that you are expecting a delivery to avoid this problem occurring. Usually, we would be notified there is a delivery issue and would email you for your instructions, normally these sorts of problems can be avoided if you contact the carrier and tell them there is an error but it's very important to act quickly to avoid the return and associated costs.