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Which DOXA SUB 300 is this?
This is the standard-production steel SUB 300 announced in August 2020, not the 2017 50th Anniversary limited edition and not the later SUB 300 Beta, Carbon or Ti5 models. DOXA traces the SUB concept to 1967 and describes it as a purpose-designed diver’s watch; that is the brand’s historical account. The 2020 watch carries the familiar cushion-shaped case and colorful dial choices, while refining the profile and finish.
The official specification lists a 42.50 mm case diameter, 45.00 mm length and 13.40 mm height. The case is 316L stainless steel, with a sapphire crystal treated for anti-reflection and luminous dive markings. Those are physical design specifications; whether the watch feels refined or bulky on a particular wrist is a matter of fit and taste.
How much slimmer is the SUB 300 than the 300T?
Launch-era comparisons put the SUB 300 at 13.4 mm thick and the SUB 300T at 14 mm—a difference of 0.6 mm. Time+Tide describes a sloped profile and box-style crystal as contributing to the slimmer impression; Time and Watches likewise highlights the reduced thickness. These are reviewers’ wearing impressions, not a guarantee that every wrist will experience the difference the same way.
The Tool Desk
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- NH35A Movement: This tactical frog watch V2 Orange is powered by the 24 Jewels NH35A self-winding movement, Assembled in Japan. Delicate and accurate.Power reserve can last for 41 hours.
- Cool Automatic Watch: Scratch resistant sapphire crystal glass with anti-reflective coating on inner surface; Stainless steel bracelet is adjustable by removing or adding links and fold over clasp with safety. A must have tactical frog watch for collection.
- Diving Watches: Double layer bezel design. Screw down lock for water tight seal and uni-directional outer stainless steel bezel to tell you "under" time easilly. Tactical frog mechanical watch is water resistant to 200M(20ATM). Suitable for professional marine activities, swimming, water sports and daily wearing.
- Luminated Watch: Green Luminious hands, scales and hour markers are featuring Swiss C3 material, which can last for at least 5 hours in dark and is able to quickly absorb and store light energy in a bright environment.
- Fashionable Style: The stylish outlook and vivid colored dial enhanced the sport and dynamic feel. A fashionable watch present for men, a must have for watch collection.
The modest numerical change matters because thickness affects how a watch sits beneath a cuff and how prominent it feels above the wrist. The 2020 SUB 300 retains a substantial 42.5 mm diameter, so it is not a small watch; the more measured case height is the refinement relative to the 300T.
What does COSC certification mean here?
DOXA lists a Swiss automatic, self-winding COSC-certified chronometer with a 38-hour power reserve and a frequency of 28,800 vibrations per hour (4 Hz). Launch coverage identifies the movement as an ETA 2824-2. Time+Tide reports a chronometer tolerance of −4/+6 seconds per day; that is the accuracy specification cited by the publication, not a result from an independent test of this particular watch.
COSC certification is a meaningful distinction in the specification: the movement has chronometer certification rather than merely being described as an automatic. It does not promise that an individual watch will maintain that rate on every wrist, in every position or after years of use.
Rank #2
- Complete Strap: This 20mm black watch band includes preinstalled quick release spring bars, providing a convenient replacement for worn, damaged or outdated wristwatch straps.
- PU Leather: Made from selected PU leather with a soft lining, this matte watch strap offers a smooth feel, vintage appearance and comfortable fit for everyday wear.
- Quick Release: Built-in quick release pins allow fast installation and removal without additional tools, while the 20mm lug width provides a precise connection.
- Adjustable Fit: The 7.1in/18cm replacement band features multiple adjustment holes and a polished stainless steel buckle for a secure, personalized wrist fit.
- Customer Support: Please measure the inner distance between your watch lugs before ordering; contact us if you have questions about size, installation or product quality.
What changes when you choose the 300T instead?
The slimmer case has a clear specification trade-off. The SUB 300 is rated to 300 m, while launch-era comparisons report 1,200 m for the SUB 300T. Time+Tide also notes that the 300T has a helium-release valve and the SUB 300 does not. These differences make the 300T the more extreme tool-watch option on paper; a higher depth rating alone does not determine which watch is right for a buyer’s real use.
A 300 m rating is ample for ordinary swimming and recreational diving when the watch is in proper condition and used within safe diving practices. It is not a substitute for a dive computer, training or current procedures, and the published rating should not be read as a claim that this article independently tested the watch underwater.
How does the bezel work?
The SUB 300 has a unidirectional bezel with an inner dive-time scale and an outer depth scale. DOXA presents the dual scale as part of the SUB’s dive-watch concept; Time and Watches notes that the 2020 SUB 300 uses metric depth markings, whereas the 300T scale is in feet. The bezel can support dive planning, including no-decompression limits, but it is not a substitute for training, a dive computer or the safety procedures appropriate to a dive.
Rank #3
- NH35A Movement: The tactical frog watch is powered by the 24 Jewels NH35A self-winding movement, Assembled in Japan. Delicate and accurate.Power reserve can last for 41 hours
- Cool Automatic Watch: Scratch resistant sapphire crystal glass with anti-reflective coating on inner surface; Stainless steel bracelet is adjustable by removing or adding links and fold over clasp with safety. A must have tactical frog watch for collection
- Diving Watches: Double layer bezel design. Screw down lock for water tight seal and uni-directional outer stainless steel bezel to tell you "under" time easilly. Tactical frog mechanical watch is water resistant to 200M(20ATM). Suitable for professional marine activities, swimming, water sports and daily wearing
- Luminated Watch: Green Luminious hands, scales and hour markers are featuring C3 material, which can last for at least 5 hours in dark and is able to quickly absorb and store light energy in a bright environment
- Fashionable Style: The stylish outlook and vivid colored dial enhanced the sport and dynamic feel. A fashionable watch present for men, a must have for watch collection
What makes the design feel more refined?
The refinement comes from a combination of measurable construction and visual restraint, rather than a change in the watch’s basic identity. The steel case has both brushed and polished surfaces, while the sapphire crystal, anti-reflective treatment and luminous markings bring a more finished presentation to the familiar diver layout. Time+Tide describes the shape and finishing favorably; that is an editorial judgment, not a universal fit verdict.
The watch remains unmistakably a DOXA diver, particularly in its bold color choices and instrument-like bezel. Six dial colors were documented at launch: Professional (orange), Sharkhunter (black), Searambler (silver), Caribbean (navy), Divingstar (yellow) and Aquamarine (turquoise). Launch coverage is not evidence that all six are currently in stock in every market.
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Launch configurations paired the watch with either a steel beads-of-rice bracelet or a rubber strap. The bracelet leans into the vintage-inspired look and gives the watch a more substantial, integrated presence; rubber shifts the appearance toward a practical sport watch and may suit water use better. DOXA’s listing specifies a 20 mm lug width and offers SUB 300-specific accessories, but confirm exact reference compatibility before buying an extra strap or bracelet.
Rank #4
- Complete Strap: This 20mm dark brown watch band includes preinstalled quick release spring bars, providing a convenient replacement for worn, damaged or outdated wristwatch straps.
- PU Leather: Selected PU leather with a soft lining creates a comfortable wrist feel, while the matte surface and subtle vintage texture deliver a refined, timeless appearance.
- Quick Release: Built-in quick release pins allow fast installation and removal without additional tools, while the 20mm lug width provides a secure and precise connection.
- Adjustable Fit: The 7.1"/18cm replacement strap features multiple adjustment holes and a polished stainless steel pin buckle for a secure, personalized fit during everyday wear.
- Customer Support: Please measure the inner distance between your watch lugs before ordering; contact us if you have questions about sizing, installation or product quality.
Think about how you will wear it most often: the bracelet for a more distinctive steel-watch look, or rubber for a lighter, more overtly aquatic setup. DOXA’s product information mentions a wetsuit extension on the clasp; whether that feature matters depends on whether you plan to wear the bracelet over exposure protection. Accessories and configurations vary by region and date.
What did the 2020 SUB 300 cost, and what is the current listed price?
Launch prices varied by market and configuration. Time+Tide reported Australian recommended retail prices of AUD 3,950 on rubber and AUD 3,990 on bracelet in 2020. Time and Watches reported Swiss launch prices of CHF 2,450 on rubber and CHF 2,490 on bracelet that year. These are historical launch figures, not current quotations.
DOXA’s US product page displayed USD 2,890 for the Professional configuration when accessed on October 8, 2026. Treat that as a dated US listing price; it does not establish worldwide pricing or current availability of other colors and configurations. Check DOXA’s current US SUB 300 listing for live product details.
Should you choose the SUB 300 or the SUB 300T?
Choose based on the balance you want rather than assuming one model is an upgrade in every respect. The SUB 300 suits someone drawn to a slightly slimmer profile, chronometer certification, metric bezel scale and a more polished vintage-inspired presentation. The 300T makes more sense for someone who values its higher stated depth rating and helium-release valve or prefers its more overtly tool-oriented character.
The most useful distinction is not 0.6 mm in isolation: it is the way the SUB 300 combines that reduced height with a lower water-resistance specification. If the slimmer profile and dial options are the draw, the SUB 300 makes a compelling everyday diver. If the 300T’s extra-rated depth and valve are relevant to your intended use, the larger margin may be worth more than the refined profile.
Quick Recap
Sources
- DOXA: SUB 300 Professional product page
- Time+Tide: 2020 DOXA SUB 300 review
- Time and Watches: DOXA SUB 300 2020
- Hodinkee: 2020 DOXA SUB 300 introduction
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.
