From Holden’s Watch Desk research
Thorn T023 Frogmantle
The Thorn T023 Frogmantle is a dive watch from Thorn: a 40 mm 316L stainless steel case, 12.3 mm thick and 46.6 mm lug to lug, with an automatic PT5000 movement and 200 m water resistance.
Going by its 46.6 mm lug to lug, it should sit within the flat top of a wrist of about 6.3 inches (16.1 cm) or larger.
Research found it at $219 list in the US (checked August 2026) and about $189–199 on the street (August 2026).
Specifications
From the research, with the sources for each group of facts. Unknown means no source confirmed it.
| The watch [1][2][3] | |
|---|---|
| Brand | Thorn |
| Reference | T023 |
| Category | Diver |
| Production | Current |
| Case and size [1][2] | |
| Case diameter | 40 mm |
| Lug to lug | 46.6 mm |
| Thickness | 12.3 mm |
| Lug width | 20 mm |
| Case material | 316L stainless steel, polished and brushed |
| Crystal | Bubble domed sapphire with inner AR coating |
| Water resistance | 200 m / 20 ATM |
| Weight | 77 g |
| Movement [1][4][2] | |
| Movement | PT5000 (Hangzhou-family ETA 2824-2 clone architecture), automatic |
| Power reserve | Unknown |
| Accuracy | +2 s/day over five days claimed by Thorn's own blog (promotional source) |
| Bracelet [1][2] | |
| Bracelet or strap | Solid 316L steel bracelet, 20 mm, 18.5 cm length |
| Clasp | Folding clasp with adjustable links |
| Price and warranty (US) [1][2] | |
| List price (US) | $219 list / $189 sale (Thorn direct); $199 at WatchDives (V2) |
| Street price (US) | $189-199 new (August 2026) |
| Used price (US) | No independent sold-comps captured (August 2026) |
| Warranty | Unknown |
Will it fit?
A watch wears comfortably when its lugs stay on the flat top of the wrist. Here is the 46.6 mm lug to lug against the flat top estimated for common wrist sizes.
| Wrist | Flat top | Fit |
|---|---|---|
| 6 in 15.2 cm | 47 mm | At the edge |
| 6.5 in 16.5 cm | 51 mm | Comfortable |
| 7 in 17.8 cm | 55 mm | Comfortable |
| 7.5 in 19.1 cm | 59 mm | Comfortable |
| 8 in 20.3 cm | 63 mm | Comfortable |
Check it against your own wrist An estimate, not a guarantee; how the method works is on the tool page.
What the research found
These are the research’s judgments, scored against Holden’s priorities, not his own words.
Strengths
- Strong spec-per-dollar: sapphire, 200 m, 2824-clone high-beat automatic under $200
- Light, compact vintage-diver proportions (40/46.6/12.3, 77 g)
- Movement service path effectively permanent via 2824 ecosystem
Weaknesses
- Openly marketed and reviewed as a vintage Tudor Submariner/Snowflake homage
- No warranty/service infrastructure or brand story beyond the homage
- Aluminum bezel insert will age with wear
Research scores, 0 to 10
| Execution and feel in the hand | 7.0 |
|---|---|
| Design identity | 4.0 |
| Value at a realistic price | 7.0 |
| Long-term ownership | 5.5 |
| Movement and engineering | 6.5 |
| Wearability and proportions | 7.5 |
| Versatility and durability | 7.0 |
| Fit with Holden's collection | 2.5 |
Also on Holden’s list
Other diver watches on his list.
- Tudor Pelagos LHD 25610TNL-0001
- Grand Seiko Spring Drive U.F.A. Ushio 300 Diver SLGB023
- Traser P67 Diver Blue 109375
- Squale 1545 Grey 1545GG.AC
- Glycine Combat Sub 42 GL0533
Sources
- Thorn T023 40mm PT5000 Automatic Dive Watch — official product page thornwatches.com · read August 26, 2026
- Thorn T023 V2 40mm Vintage Sub Diver Watch watchdives.com · read August 26, 2026
- The NEW Thorn T023 v3 Dive Watch | Is this vintage style HYPE or the REAL deal? (YouTube) youtube.com · read August 26, 2026
- Thorn T023 Review — The Modern Revival of a Vintage Dive Watch (brand blog) thornwatches.com · read August 26, 2026
- Best Tudor Snowflake homage — Thorn T023 Watch Review (YouTube) youtube.com · read August 26, 2026
Personal research, not a source of truth. Spotted an error? Email a correction.