ThornT015
Homage to the Seiko Tuna
about$219
Regular price at the brand's own website, checked 1 Nov 2026. Marketplace prices change often.
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The Thorn T015 Black Titanium Shroud Diver is a homage to the Seiko Tuna, with a 47 mm case, 2.4 mm smaller. It uses an automatic movement and is water resistant to 200 m. It costs about $219 at the official store.
Side by side with the original
Compared with reference SBBN047. Values marked ≈ are estimates, such as a reviewer's measurement.
| Spec | T015 | Tuna (SBBN047) | Difference |
|---|---|---|---|
| Case diameter | 47 mm | 49.4 mm | −2.4 mm |
| Lug-to-lug | Not published | 49.4 mm | Can't compare |
| Thickness | 14.2 mm | 16.3 mm | −2.1 mm |
| Lug width | Not published | Not published | Can't compare |
| Water resistance | 200 m | 1000 m | |
| Movement | Automatic, NH35A | Quartz, 7C46 | |
| Power reserve | Not published | Not published | |
| Crystal | Sapphire | Sapphire | |
| Bezel | 120-tooth unidirectional rotating bezel, Two-tone aluminium insert with a BGW9 lume dot at 12 | Unidirectional rotating bezel | |
| Case material | Grade 2 titanium with a vacuum-plated black finish | One-piece (monobloc) case with black super-hard coating | |
| Lume | Swiss BGW9 super-luminous on dial, hands and bezel insert | LumiBrite on hands, indexes and bezel | |
| Bracelet | Genuine cowhide leather strap, 22 mm, double stitched | Black silicone strap | |
| Weight | Not published | 118.5 g |
The original
Seiko
Tuna
Reference SBBN047, prospex marinemaster professional 1000 m, black dial, black silicone strap
- Case
- 49.4 mm
- Lug-to-lug
- 49.4 mm
- Thickness
- 16.3 mm
- Water resistance
- 1000 m
- Movement
- Quartz, 7C46
- List price
- Not published
Why it scores as it does
Proportions and movement are computed from specs. Design details and functions are judged from the brand's official images. How we score
Lug-to-lug is neither published nor measured for one of the two watches, so there is not enough data to score.
Proportions— / 30
- Case diameter2.4 / 122.4 mm apart
- Lug-to-lug0 / 8Not published, left out
- Thickness1.8 / 62.1 mm apart
- Lug width0 / 4Not published, left out
Design signatures— / 40
- Shroud around the case10 / 10A black-coated titanium shroud surrounds the case, as in the official images.
- Round lug-less monobloc case5 / 10Round shrouded case with the lugs under it, but a screwed shroud rather than a one-piece case.
- Cut-outs in the shroud giving access to the bezel2 / 4The shroud is cut away around the knurled bezel, with different cut-out shapes.
- Brushed hands in the 1975 style0 / 6Sword hands with an orange-tipped arrow seconds hand; not the original's hands.
- Matte black dial with large white indices3 / 6Black dial with large lume indices, but the 12, 3, 6 and 9 markers carry red frames.
- Unidirectional dive bezel2 / 4The brand lists a unidirectional bezel, but the insert has a compass scale rather than dive minutes.
Functions and materials— / 20
- Complications4 / 8No date window in the official images; the original has day and date. The store title says GMT but the dial shows no GMT hand.
- Bezel action4 / 4Unidirectional bezel per the brand, as on the original.
- Case and bezel materials2 / 4Black-coated titanium; the original is a black-coated one-piece steel case.
- Crystal shape and date window4 / 4Sapphire crystal, as on the original.
Movement type— / 10
- Movement type0 / 10Different movement type.
What reviewers and owners say
We haven't read enough independent reviews of this model to summarise them yet.
Good
- Black-coated titanium case
- BGW9 lume on dial, hands and bezel insert
- Dual-curved sapphire crystal (brand)
- Leather strap with double stitching
Less good
- 47 mm and 14.2 mm thick
- Brand lists no lug-to-lug length
- No independent review of this model was found
- Store title and spec text disagree on the movement
Compare
Sources
Checked 1 Nov 2026. Every figure on this page comes from one of these pages.