Seiko Tuna homages
Shrouded professional divers, including the Emperor Tuna, Street Tuna and Baby Tuna.
49.4 mm across5 homages
See three to start with
How to recognise one
Six marks make the look. The count says how many of the 5 homages keep each one.
Black shroud
A thick black shroud wraps the whole case and the bezel.
Dive bezel
A bezel with white numerals every ten minutes and a lumed triangle at 12.
Triangle at 12
A lumed triangle at 12 on the dial.
Large round plots
Big lumed circles mark the other hours.
Day and date at 3
A window at 3 shows the day and the date.
Crown at 4
The crown sits at 4 and is tucked into the shroud.
Each close-up covers about 12.5 mm of watch, using the listed case width and estimated photo edges.
Three to start with
Picked from the record by marks kept, price and size, each sold under its own maker's name, not as a Seiko.
Addiesdive MY-H5
about £112 $149, seen 2 Oct47.5 mm
Lowest price. The lowest price listed here.
Steeldive SD1975
about £120 $160, seen 2 Oct47.5 mm
Nearest in size. 47.5 mm across, 1.9 mm narrower than the 49.4 mm Seiko.
Steeldive SD1975S
about £165 $219.99, seen 2 Oct47.5 mm
47.5 mm across, NH35.
The other 2, to scale
Most marks kept first.
- Heimdallr HMSX11
Price and size not listed yet
- Heimdallr Titanium Tuna
Price and size not listed yet
Drawn to scale by listed case width.
Original specifications
Sizes and specifications apply to the version named below. Other versions can differ.
SBDX014
Exact reference SBDX014 supplied by assignment.
| Specification | Value | Sources and notes |
|---|---|---|
| Case width | 52.4 mm | Seiko Prospex Marinemaster SBDX014 | WatchOutzSeiko Prospex Sea Date 52.4 mm | Chronotick Sources agree. Diameter of outer shroud as labeled. |
| Lug to lug | 53.5 mm | Seiko Prospex Marinemaster SBDX014 | WatchOutzSeiko Prospex Sea Date 52.4 mm | Chronotick Sources agree. The body-read sources Seiko Prospex Marinemaster SBDX014 | WatchOutz, Seiko Prospex Sea Date 52.4 mm | Chronotick identify reference SBDX014 and agree on lug to lug mm at 53.5 mm. |
| Thickness | 17.2 mm | Seiko Prospex Marinemaster SBDX014 | WatchOutzSeiko Prospex Sea Date 52.4 mm | Chronotick Sources agree. The body-read sources Seiko Prospex Marinemaster SBDX014 | WatchOutz, Seiko Prospex Sea Date 52.4 mm | Chronotick identify reference SBDX014 and agree on thickness mm at 17.2 mm. |
| Lug width | 22 mm | Seiko Prospex Marinemaster SBDX014 | WatchOutzSeiko Prospex Sea Date 52.4 mm | Chronotick Sources agree. The body-read sources Seiko Prospex Marinemaster SBDX014 | WatchOutz, Seiko Prospex Sea Date 52.4 mm | Chronotick identify reference SBDX014 and agree on lug width mm at 22 mm. Distance between lugs. |
| Movement calibre | 8L35 | Seiko Prospex Marinemaster SBDX014 | WatchOutzSeiko Prospex Sea Date 52.4 mm | Chronotick Sources agree. The body-read sources Seiko Prospex Marinemaster SBDX014 | WatchOutz, Seiko Prospex Sea Date 52.4 mm | Chronotick identify reference SBDX014 and agree on movement calibre at 8L35. |
| Case material | Titanium | Seiko Prospex Marinemaster SBDX014 | WatchOutzSeiko Prospex Sea Date 52.4 mm | Chronotick Sources agree. The body-read sources Seiko Prospex Marinemaster SBDX014 | WatchOutz, Seiko Prospex Sea Date 52.4 mm | Chronotick identify reference SBDX014 and agree on case material at Titanium. |
| Water resistance | 1000 m | Seiko Prospex Marinemaster SBDX014 | WatchOutzSeiko Prospex Sea Date 52.4 mm | Chronotick Sources agree. Both pages repeat manufacturer rating; neither independently tested it. |
| Power reserve | 50 hours | Seiko Prospex Marinemaster SBDX014 | WatchOutzSeiko Prospex Sea Date 52.4 mm | Chronotick Sources agree. The body-read sources Seiko Prospex Marinemaster SBDX014 | WatchOutz, Seiko Prospex Sea Date 52.4 mm | Chronotick identify reference SBDX014 and agree on power reserve hours at 50 hours. |
Sources and unconfirmed details
- Water resistance is a maker rating repeated by retailers, not an independent pressure-test result.
- Seiko Prospex Marinemaster SBDX014 | WatchOutz, read 2026-10-07
- Seiko Prospex Sea Date 52.4 mm | Chronotick, read 2026-10-07
SBBN047Shown in the photograph
Manifest pictured scope SBBN047 quartz Tuna (1000m, black shroud, silicone strap). Existing family candidates are excluded.
| Specification | Value | Sources and notes |
|---|---|---|
| Case width | 49.4 mm | Seiko Prospex SBBN047 specifications One primary source. Official horizontal 49.4 mm and vertical 49.4 mm case dimensions. Vertical overall length used as lug span; no mechanical power reserve for battery quartz. |
| Lug to lug | 49.4 mm | Seiko Prospex SBBN047 specifications One primary source. Official horizontal 49.4 mm and vertical 49.4 mm case dimensions. Vertical overall length used as lug span; no mechanical power reserve for battery quartz. |
| Thickness | 16.3 mm | Seiko Prospex SBBN047 specifications One primary source. Official horizontal 49.4 mm and vertical 49.4 mm case dimensions. Vertical overall length used as lug span; no mechanical power reserve for battery quartz. |
| Lug width | 22 mm | Original Seiko R01X011M9 strap compatible with SBBN047 One cited source. Official Seiko dealer explicitly lists SBBN047 compatibility and 22 mm lug width. |
| Movement calibre | 7C46 | Seiko Prospex SBBN047 specifications One primary source. Official horizontal 49.4 mm and vertical 49.4 mm case dimensions. Vertical overall length used as lug span; no mechanical power reserve for battery quartz. |
| Water resistance | 1000 m | Seiko Prospex SBBN047 specifications One primary source. Official horizontal 49.4 mm and vertical 49.4 mm case dimensions. Vertical overall length used as lug span; no mechanical power reserve for battery quartz. |
| Power reserve | Not confirmed | Not applicable as a mechanical winding reserve. Quartz 7C46 official battery life is approximately five years, distinct from power reserve hours. |
Sources and unconfirmed details
- Not applicable as a mechanical winding reserve. Quartz 7C46 official battery life is approximately five years, distinct from power reserve hours.
- Seiko Prospex SBBN047 specifications, read 2026-10-07
- Original Seiko R01X011M9 strap compatible with SBBN047, read 2026-10-07
More about the Tuna
Lay a homage over the SeikoAny of the 5, laid over the original at one scale
Lay a homage over the Seiko
Slide to fade from one watch to the other and compare the case shapes. The figures below describe the version shown in the photograph.
49.4Seiko Tuna
47.5Addiesdive MY-H5
40 mm placeholderHeimdallr HMSX11
40 mm placeholderHeimdallr Titanium Tuna
47.5Steeldive SD1975
47.5Steeldive SD1975SPhotos use listed case widths and automatic case-edge readings. The readings have not been manually audited. Photo proportions stay unchanged. Perspective and lug length can differ.Width unknown for one or both watches. The 40 mm placeholder does not show their true relative size. Photo proportions stay unchanged. Perspective and lug length can differ.Width unknown for one or both watches. The 40 mm placeholder does not show their true relative size. Photo proportions stay unchanged. Perspective and lug length can differ.Photos use listed case widths and automatic case-edge readings. The readings have not been manually audited. Photo proportions stay unchanged. Perspective and lug length can differ.Photos use listed case widths and automatic case-edge readings. The readings have not been manually audited. Photo proportions stay unchanged. Perspective and lug length can differ.
Seiko Tuna photo: SBBN047. Addiesdive MY-H5 photo: MY-H5 Tuna, black dial, steel bracelet.Case width unknown. Shown with a 40 mm placeholder.
Seiko Tuna photo: SBBN047. Heimdallr HMSX11 photo: Heimdallr 1KM Tuna (HMSX11 class), lume triangle bezel, black dial.Case width unknown. Shown with a 40 mm placeholder.
Seiko Tuna photo: SBBN047. Heimdallr Titanium Tuna photo: Titanium Tuna Can black dial, black rubber strap.47.5 mm, 1.9 mm narrower than the Seiko
Seiko Tuna photo: SBBN047. Steeldive SD1975 photo: SD1975 tuna, black dial, steel bracelet.47.5 mm, 1.9 mm narrower than the Seiko
Seiko Tuna photo: SBBN047. Steeldive SD1975S photo: SD1975S bronze tuna, black dial, orange rubber strap.
SBBN047, specifications and sources
| Measure | Seiko | Addiesdive MY-H5 |
|---|---|---|
| Case width | 49.4 mm | 47.5 mm |
| Lug to lug | 49.4 mm | Not listed yet |
| Thickness | 16.3 mm | 15 mm |
| Lug width | 22 mm | 22 mm |
| Movement | 7C46 | NH35 or Miyota 8215 |
| Power reserve | Not listed yet | Not listed yet |
| Water | 1000 m | 300 m |
| Price | Not tracked here | about £112 $149, seen 2 Oct |
Side view
Copies
Not compared yet
Gives it away
No difference noted