SeesternS478
Homage to the Tudor Black Bay GMT
about$330
Regular price at seesternwatches.com, checked 31 Oct 2026. Marketplace prices change often.
We may earn a commission from these official stores, at no extra cost to you. It never affects scores or rankings. Affiliate disclosure
The Seestern S478 is a homage to the Tudor Black Bay GMT, with a 39.5 mm case, 1.5 mm smaller. It uses an automatic movement and is water resistant to 100 m. It costs about $330 at the official store.
Side by side with the original
Compared with reference M79830RB-0001. Values marked ≈ are estimates, such as a reviewer's measurement.
| Spec | S478 | Black Bay GMT (M79830RB-0001) | Difference |
|---|---|---|---|
| Case diameter | 39.5 mm | 41 mm | −1.5 mm |
| Lug-to-lug | Not published | Not published | Can't compare |
| Thickness | 12 mm | ≈ 14.5 mm | −2.5 mm |
| Lug width | Not published | Not published | Can't compare |
| Water resistance | 100 m | 200 m | |
| Movement | Automatic, Peacock SL3032 | Automatic, MT5652 | |
| Power reserve | 35 h | 70 h | |
| Crystal | Sapphire | Not published | |
| Bezel | 24-hour scale bezel (from the official images; the brand does not describe its action) | Bidirectional rotating, 24-hour scale, Matte burgundy and blue aluminium | |
| Case material | 316L stainless steel | Steel | |
| Lume | Not published | Not published | |
| Bracelet | Stainless steel three-link bracelet | Riveted steel | |
| Weight | Not published | Not published |
- ≈ Black Bay GMT, Thickness: median of 3 agreeing independent measurements (14.5–14.6 mm); the maker does not publish it.
The original
Tudor
Black Bay GMT
Reference M79830RB-0001, black dial, burgundy and blue bezel, steel bracelet
- Case
- 41 mm
- Lug-to-lug
- Not published
- Thickness
- ≈ 14.5 mm
- Water resistance
- 200 m
- Movement
- Automatic, MT5652
- List price
- $5,275
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 diameter6 / 121.5 mm apart
- Lug-to-lug0 / 8Not published, left out
- Thickness1 / 62.5 mm apart
- Lug width0 / 4Not published, left out
Design signatures— / 40
- Burgundy and blue 24-hour bezel6 / 12The .W version has a blue and red 24-hour bezel; the red is brighter than burgundy. The other versions use a single colour or black and red.
- Snowflake hour and minute hands4.5 / 9Arrow-shaped hour hand with a square tip and a sword minute hand, a snowflake-like shape but not the original's.
- Red snowflake-tipped GMT hand0 / 5The 24-hour hand is white and lume with a square tip, not red.
- Riveted steel bracelet0 / 6Plain three-link brushed bracelet with no rivets.
- Matte black domed dial2 / 4The .K version has a black dial; the white and yellow versions do not follow this.
- Applied silver hour markers2 / 2Applied round and bar markers with lume, and a triangle at 12.
- Large screw-down crown2 / 2Screw-down crown with a signed S mark.
Functions and materials— / 20
- Complications4 / 8Date and a 24-hour hand like the original; the brand text does not mention the GMT function and does not say how the hands set.
- Bezel action2 / 4The brand does not describe the bezel; the images show a coin-edge 24-hour bezel that may rotate.
- Case and bezel materials2 / 4316L steel; the bezel insert material is not stated, and the original's is aluminium.
- Crystal shape and date window2 / 4Domed sapphire crystal as stated; the original's crystal is not recorded.
Movement type— / 10
- Movement type10 / 10Same movement type.
What reviewers and owners say
We haven't read enough independent reviews of this model to summarise them yet.
Good
- Domed sapphire crystal and exhibition case back
- Peacock SL3032 automatic movement stated by the brand
- Folding buckle with micro-adjust
- Four dial and bezel combinations
Less good
- The bracelet is not riveted and the GMT hand is not red, so it matches fewer of the original's details
- No hands-on review of this model was found
- Brand text does not describe the GMT function or the bezel
Versions and colours
- Black dial, black and red 24-hour bezelIts own colourway, not on the originalabout $340
- White dial, blue and red 24-hour bezelFollows the Black Bay GMT M79830RB-0001 (black dial, burgundy and blue bezel, steel bracelet)about $340
- White dial, blue 24-hour bezelIts own colourway, not on the originalabout $330
- Yellow dial, black 24-hour bezelIts own colourway, not on the originalabout $330
Compare
Sources
Checked 31 Oct 2026. Every figure on this page comes from one of these pages.