The DOXA SUB 300 Carbon pairs a forged-carbon exterior with a titanium pressure chamber, giving this 300-meter automatic dive watch a material story—and a wrist feel—that differs from a conventional steel-cased diver. DOXA lists a 42.50 mm diameter, 45.00 mm length and 13.40 mm height. Reviewers describe it as notably light, but their impressions and any quoted weight apply to specific variants, not automatically to every SUB 300 Carbon.
What makes the SUB 300 Carbon different?
Carbon is not the whole case. DOXA describes a forged-carbon exterior surrounding a titanium chamber, with a screw-down case back. The construction combines a carbon outer structure with titanium where the pressure-resistant inner case and back are concerned; it should not be described simply as a solid-carbon watch.
DOXA says the SUB 300 first appeared in carbon in 2021, more than 50 years after the model’s origins, and calls this an unlimited carbon edition. That is the brand’s own account of the model’s place in its history.
Specifications and current US price
| Specification | DOXA listing |
|---|---|
| Case construction | Forged-carbon exterior, titanium chamber and screw-down case back |
| Diameter | 42.50 mm |
| Length | 45.00 mm |
| Height | 13.40 mm |
| Water resistance | 30 ATM / 300 meters / 984 feet |
| Movement | Swiss automatic, self-winding, COSC-certified chronometer |
| Power reserve | 38 hours |
| Frequency | 28,800 vibrations per hour (4.0 Hz) |
| Other functions and features | Date, sapphire crystal, unidirectional carbon bezel with meter markings |
| Strap and clasp | FKM rubber strap, black PVD-coated folding clasp and ratcheting wetsuit extension |
| Lug width | 20 mm |
These are manufacturer specifications on DOXA’s US product page, checked in 2026. The page displayed a sale price of $4,390 in the US when checked; it is a changeable listing, not a guaranteed ongoing price or a price for every colorway or market. Check the selected configuration and its current regional listing before buying.
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- LIMITED-EDITION DIVE WATCH WITH PREMIUM MATERIALS - The Aquadeep Submerge Carbon elevates the Aquadeep platform with premium materials and limited-edition exclusivity. Developed for enthusiasts seeking a more distinctive and collectible timepiece, it blends professional dive-watch functionality with contemporary design and advanced material technology.
- FORGED CARBON FIBER DIAL WITH HIGH-VISIBILITY DETAILS - At the center of the Submerge Carbon is a forged carbon fiber dial that creates a naturally layered texture unique to each watch. Paired with bright yellow accents for enhanced readability, the dial offers a bold and technical appearance inspired by modern performance equipment.
- NH37 AUTOMATIC MOVEMENT FOR MODERN MECHANICAL PERFORMANCE - The Aquadeep Submerge Carbon is powered by the Japanese NH37 automatic movement, providing dependable self-winding operation and consistent performance. Designed for mechanical watch enthusiasts, it combines reliability with the enduring appeal of an automatic movement.
- TITANIUM CASE WITH CARBON BEZEL TECHNOLOGY - Combining a DLC-coated titanium case with a carbon bezel, the Submerge Carbon showcases a more advanced material package than the standard Aquadeep. The lightweight construction enhances comfort while reinforcing the watch's modern, performance-oriented character.
- PREMIUM COLLECTOR'S DIVE WATCH DESIGN - With 300 meters of water resistance, the Submerge Carbon is built for real-world diving while emphasizing exclusivity, modern materials, and distinctive aesthetics. Rather than focusing on a higher depth rating, it differentiates itself through forged carbon construction, limited-edition status, and a more premium overall execution.
What does the SUB 300 Carbon feel like on wrist?
Reviewer impressions
Fratello’s June 28, 2021 hands-on review of the production Divingstar model describes it as extremely light and comfortable during wear and travel. That is one reviewer’s experience, not a fit guarantee for every wrist or personal preference.
Hodinkee’s coverage of the limited Aqua Lung US Divers edition likewise describes the watch as very light in hand and on wrist. It reports DOXA’s total-weight figure of 87 g for that configuration, including its cut-to-fit strap and clasp. That number belongs to the limited edition as reported; it should not be assumed for the current Professional or another strap and clasp combination.
Rank #2
- 𝗛𝗘𝗔𝗩𝗬 𝗗𝗨𝗧𝗬, 𝗛𝗜𝗚𝗛 𝗣𝗘𝗥𝗙𝗢𝗥𝗠𝗔𝗡𝗖𝗘 𝗗𝗜𝗩𝗘 𝗪𝗔𝗧𝗖𝗛: Built for diving enthusiasts, this high-performance watch is designed to withstand depths of up to 500 meters, making it ideal for high-impact water sports, scuba diving, and saturation diving.
- 𝗘𝗫𝗖𝗘𝗣𝗧𝗜𝗢𝗡𝗔𝗟 𝗟𝗜𝗚𝗛𝗧𝗪𝗘𝗜𝗚𝗛𝗧 𝗗𝗨𝗥𝗔𝗕𝗜𝗟𝗜𝗧𝗬: Crafted from Grade II Titanium with a sandblasted finish, our timepiece is 40% lighter than steel, offering ultimate comfort without compromising on durability. Hypoallergenic and highly resistant to corrosion from sea water and chlorine, it's built to withstand the toughest conditions while maintaining its sleek appearance.
- 𝗨𝗡𝗠𝗔𝗧𝗖𝗛𝗘𝗗 𝗖𝗟𝗔𝗥𝗜𝗧𝗬 & 𝗥𝗘𝗔𝗗𝗔𝗕𝗜𝗟𝗜𝗧𝗬 𝗢𝗙 𝗧𝗜𝗠𝗘: Experience unparalleled clarity and readability with our double dome sapphire crystal glass. No matter the angle, this feature ensures that time is easily readable, allowing you to stay on track with confidence and precision.
- 𝗨𝗟𝗧𝗜𝗠𝗔𝗧𝗘 𝗖𝗢𝗠𝗙𝗢𝗥𝗧 𝗢𝗡 𝗬𝗢𝗨𝗥 𝗪𝗥𝗜𝗦𝗧: Our timepiece comes with a rubber strap designed for unparalleled comfort, flexibility, and adaptability to your wrist's contours. Perfect for individuals leading active lifestyles or seeking all-day comfort, it ensures a snug and pleasant fit every time.
- 𝗥𝗘𝗡𝗢𝗪𝗡𝗘𝗗 𝗕𝗥𝗔𝗡𝗗 𝗔𝗡𝗗 𝗖𝗢𝗟𝗟𝗘𝗖𝗧𝗜𝗢𝗡: As part of the esteemed UNDONE brand, the Aquadeep Submerge belongs to a collection designed for serious divers and underwater enthusiasts.
How to judge fit for yourself
The listed 42.50 mm diameter is only one part of fit. DOXA also gives a 45.00 mm length and 13.40 mm height, but those measurements cannot tell you how the watch will sit on your wrist. Try the actual colorway and strap if possible, paying attention to how the case spans your wrist, how the height feels under a sleeve, and whether the strap can be adjusted comfortably. The 20 mm lug width identifies the strap connection width, not universal compatibility with every third-party strap or clasp.
What do the dive-watch specifications establish?
DOXA rates the watch to 300 m (30 ATM / 984 ft) and lists a unidirectional bezel with meter markings, a screw-down case back and a ratcheting wetsuit extension. Those are useful stated specifications, but a depth rating is not a recommendation to dive without suitable equipment, training and adherence to safe diving practice. Confirm the exact variant and intended use rather than treating the rating alone as proof of suitability for a particular dive.
Rank #3
- Unique Carbon Fiber Dial: Each dial is crafted from carbon fiber, ensuring a unique, pattern exclusive to your watch. This high-tech material adds a distinctive style for both underwater missions and surface-level sophistication
- Rugged Style: Featuring an angular, multi-faceted case, this watch delivers a tough tool-watch aesthetic built for demanding environments. Its robust construction is ideal for professional diving, underwater exploration, and outdoor adventures
- Premium Materials: With accurate 9015 automatic movement, BGW9 lume, sapphire crystal, screw-down crown and case back, 316L stainless steel. Its robust construction handles extended diving, sailing, and harsh conditions with lasting reliability
- Lume & Waterproof: 200m water resistance meets BGW9 super-lume for true dive readiness. This combination ensures clear visibility in deep or murky water and reliability during extended underwater exploration
- Dimensions: Featuring a 11.5 mm thin profile, 6.5 mm crown, 40 mm case, 45.8 mm lugs to lugs, and total weight of 144 g, 220 mm in total length with 20 mm lug width, fitting wrists 6"–8.5"
The movement is listed as a Swiss automatic, self-winding COSC-certified chronometer, with a 38-hour power reserve and 28,800 vph frequency. The reserve is the stated running time when fully wound; it is not a measure of how accurately the watch will perform for an individual wearer outside its certification context.
What to verify before buying
- Reference and colorway: Confirm that the listing is the SUB 300 Carbon Professional configuration you want. Price and availability can vary by variant and region.
- Fit: Compare the 42.50 mm diameter, 45.00 mm length and 13.40 mm height with how the case sits on your wrist; specifications cannot replace trying it on.
- Included strap and clasp: The official configuration lists a 20 mm FKM strap, folding clasp and wetsuit extension. Check what is included with the specific reference, especially if you expect the limited edition’s cut-to-fit setup.
- Current US listing: The $4,390 sale price was the displayed US price when checked in 2026. Verify the live price, availability and seller for your selected configuration.
- Strap replacements: A 20 mm width alone does not establish third-party compatibility. Check end shape, strap thickness and clasp arrangement before ordering a replacement.
How to assess it against another dive watch
Compare the actual features rather than relying on the carbon label alone. Against a conventional steel-cased diver, the SUB 300 Carbon’s stated distinction is its forged-carbon exterior and titanium chamber; reviewer accounts suggest a light wearing experience, but do not provide a directly comparable weight for every variant. For fit, compare case length, diameter, height and strap setup. For use, compare the stated water resistance, bezel and movement details, then consider whether the particular watch and your training suit the diving you plan to do. Finally, compare the same market and configuration: DOXA’s US listing is not a global price benchmark.
Quick Recap
Best Value
- Carbonox+
- Sapphire Crystal
- 316L Stainless Steel Back
- Swiss Automatic - SELLITA SW220-1
Rank #4
- Self-winding automatic movement - an Eco-friendly choice for discerning customer. Powered by everyday movement of your arm
- Automatic self-winding movement with analog display and sapphire crystal dial window
- Date calendar, water-resistant, luminous, chronograph
- Black rubber carbon fiber case with black dial
- Water resistant to 50 ATM / 500 meters / 1650 feet : suitable for professional marine activity serious surface water sports and skin diving
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
