Introduction
When Doxa revived the SUB 300 in 2020, the watch world collectively exhaled. The brand that defined the modern dive watch in the 1960s—with its iconic orange dial, beads-of-rice bracelet, and patented no-decompression scale—was back. But the reissue, while faithful, measured 42.5mm. For collectors with smaller wrists or a preference for vintage proportions, it was a near-miss. Enter the Doxa SUB 300 Beta (ref. 830.10.351.10), a 40mm reinterpretation that captures the spirit of the original without sacrificing wearability.
The Beta isn't just a downsized version; it's a thoughtful re-engineering. The case retains the signature cushion shape, the bezel still features the iconic orange and black insert, and the dial layout remains pure Doxa. Yet the proportions are tighter, the lugs shorter, and the overall presence more subdued. It's the watch for the collector who loves the SUB 300's heritage but wants something that disappears on the wrist—a tool watch that doesn't shout.
In this review, we'll dive into the history, specs, movement, and real-world wear of the Doxa SUB 300 Beta. Whether you're a seasoned diver or a desk-diver with an eye for horological history, this watch deserves a spot on your radar.
Manufacture History
Doxa was founded in 1889 in Le Locle, Switzerland, and gained fame in the 1960s with the SUB 300, one of the first purpose-built dive watches. The brand's orange dial and patented no-decompression bezel became synonymous with professional diving. After a period of dormancy, Doxa was revived in the 2010s and has since reissued its classic models with modern updates.
Movement
The Doxa SUB 300 Beta is powered by the Sellita SW200-1, a reliable automatic movement based on the ETA 2824-2 architecture. It beats at 28,800 vph, has 26 jewels, and offers a 38-hour power reserve. While not in-house or COSC-certified, the SW200-1 is a proven workhorse that is easy to service and regulate. The rotor is decorated with Doxa's logo, visible through the display caseback. For a tool watch at this price point, the movement is more than adequate.
Specifications
- Case diameter: 40mm
- Case thickness: 12.5mm
- Lug-to-lug: 48mm
- Case material: Stainless steel
- Crystal: Sapphire with double anti-reflective coating
- Water resistance: 300m (1000ft)
- Lume: Super-LumiNova X1
- Bracelet/Strap: Beads of rice stainless steel bracelet with folding clasp
- Clasp type: Folding clasp with safety release
Wrist Feel
The Doxa SUB 300 Beta is a masterclass in ergonomics. At 40mm wide and 48mm lug-to-lug, it sits perfectly on wrists from 6.5 to 7.5 inches. The beads-of-rice bracelet is supple and conforms to the wrist without pulling hair, and the folding clasp is low-profile. The case thickness of 12.5mm is moderate, but the domed crystal adds a touch of vintage charm. Despite its 300m water resistance, the watch feels light and balanced—never top-heavy. The crown is signed and easy to grip, and the bezel action is crisp with 120 clicks. This is a watch you can wear all day, from the office to the ocean, without fatigue.
Accuracy
The Sellita SW200-1 inside the Beta is typically regulated to within -7/+7 seconds per day. In real-world use, expect around +5 to +10 seconds per day depending on position and activity. It's not COSC-certified, but for a tool watch at this price point, the accuracy is more than adequate. A quick regulation by a watchmaker can bring it to within a few seconds if desired.
Occasions
The Beta is versatile enough for daily wear, sport, and travel. Its 300m water resistance makes it a legitimate dive watch, while the compact size and comfortable bracelet allow it to slide under a dress shirt cuff. The orange dial is bold but not obnoxious—it's a statement without being a shout.
Wrist Presence
3.5/5 — The Beta is understated compared to its 42.5mm sibling. The orange dial still pops, but the smaller case and shorter lugs make it less imposing. It's a conversation starter for those in the know, but it won't dominate a room.
Reference Variants
The Doxa SUB 300 Beta is available in several dial colors: Professional (orange), Sharkhunter (black), Caribbean (silver with blue bezel), and Aquamarine (blue). All share the same 40mm case and beads-of-rice bracelet. The reference 830.10.351.10 is the orange dial version.
Family References
The Beta sits below the standard SUB 300 (42.5mm) and SUB 300T (42.5mm) in Doxa's lineup. It also shares DNA with the SUB 200 (39mm), though the SUB 200 is a simpler, less expensive model.
Other Notable Models by Doxa
Doxa's catalog includes the SUB 300T Professional, SUB 200, SUB 600T, and SUB 1500T. The brand is also known for its limited editions and collaborations with dive professionals.
Similar Watches
If you like the Doxa SUB 300 Beta, consider the Tudor Black Bay 58 (39mm, similar vintage dive watch), Omega Seamaster 300 (41mm, more modern), or Longines Legend Diver (42mm, compressor style).
Homages
For a budget-friendly alternative, the Steinhart Ocean 39 Vintage Orange offers a similar look at around $450. The Zelos Mako 300 is another microbrand option with a cushion case and orange dial.
Investment Value
The Doxa SUB 300 Beta has an MSRP of $2,490. Pre-owned prices range from $2,000 to $2,400. The trend is stable; it's not a collector's item that will appreciate rapidly, but it holds its value well. Buy it to wear and enjoy.
Service Interval
Doxa recommends service every 5 years. A full service costs approximately $500 at an authorized center or a qualified independent watchmaker. The Sellita movement is easy to service, so you're not locked into the brand.
Pros and Cons
Pros: Perfect 40mm size, iconic design, 300m water resistance, comfortable bracelet.
Cons: Movement lacks in-house prestige, 38-hour power reserve, no quick-adjust clasp, orange dial may be too loud for some.
Final Verdict
The Doxa SUB 300 Beta is a thoughtful evolution of a classic. It retains the soul of the original while addressing the biggest complaint: size. If you've been eyeing the SUB 300 but found it too large, the Beta is your answer. It's a tool watch with heritage, charm, and genuine dive capability—all in a wrist-friendly 40mm package.
