BewristHomage watches, measured
Steeldive SD1975, tuna, black dial, steel bracelet
SD1975, tuna, black dial, steel bracelet

Steeldive SD1975

A homage of the Seiko Tuna

about £120 $160, seen 2 Oct

At steeldives.com, sold out on 2 Oct. For the SD1975 blue dial, 5-link bracelet version.

Size
47.5 mm across, 1.9 mm narrower than the Seiko
Movement
NH35, automatic
Look
Not compared mark by mark yet
Gives it away
1.9 mm narrower than the Seiko, 47.5 mm against 49.4 mm
Compare with another homage

No shop links yet.

Homages of the Seiko Tuna you can buy

Against the Seiko

Seiko Tuna SBBN04749.4Seiko Tuna SBBN047
Steeldive SD197547.5Steeldive SD1975

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.

47.5 mm, 1.9 mm narrower than the Seiko
Seiko Tuna SBBN047 photo: SBBN047. Steeldive SD1975 photo: SD1975 tuna, black dial, steel bracelet.

The Seiko drawn is the SBBN047.

What gives it away

  • 1.9 mm narrower than the Seiko, 47.5 mm against 49.4 mm

  • Black shroud

    Not compared yet.

  • Dive bezel

    Not compared yet.

  • Triangle at 12

    Not compared yet.

  • Large round plots

    Not compared yet.

  • Day and date at 3

    Not compared yet.

  • Crown at 4

    Not compared yet.

Seiko left, SD1975 right.

Everything else

Every spec7 listed, each with where it came from

Every spec we have

From sellers. Each figure links to where it was found.

For the SD1975 version.

Case width
47.5 mmsteeldives.com, 2 Oct
Lug to lug
44 mmsteeldives.com, 2 Oct
Thickness
15 mmsteeldives.com, 2 Oct
Lug width
22 mmsteeldives.com, 2 Oct
Movement calibre
NH35steeldives.com, 2 Oct
Case material
316L stainless steelsteeldives.com, 2 Oct
Water resistance
300 msteeldives.com, 2 Oct
The movementTime Module NH35, in plain words

The movement, in plain words

Steeldive lists the NH35 for the SD1975.

How it runs. An automatic. Wearing it winds it.

Beat. It beats 21,600 times an hour, 6 a second, so the seconds hand sweeps in small steps.

Setting the time. The seconds hand stops when you pull the crown out, so you can set it to the second.

On your wrist47.5 mm across, 15 mm thick, on a wrist your size

How it sits on your wrist

Set your wrist circumference to compare the 47.5 mm case with a schematic wrist. The ellipse estimates wrist width and shape. It cannot predict your fit.

17.0 cm6.7 in around

This wrist model is about 56 mm across. The case spans 85% of that estimated width. Lug to lug is unknown, so no lug extent is drawn.

Wrap a strip of paper round your wrist just below the bone, mark where it meets and measure it.

47.5 mm case Wrist model about 56 mm across
Schematic section, with a 10 mm grid. The ellipse approximates wrist anatomy from circumference. Your wrist shape, lug curve and fit will differ.

How tall it stands

15 47.5 wide

The side view uses listed dimensions. Case shape and lug curve are schematic.

Lug to lug is not listed yet, so the drawing stops at the case.

Side views to scale against other Seiko Tuna homages.

  1. Addiesdive MY-H515 mm
  2. Steeldive SD1975S15 mm
  3. Steeldive SD197515 mm
Earlier prices3 seen before, with the date

  • steeldives.com $160 (about £120), seen 2 Oct, sold out

    SD1975 blue dial, 5-link bracelet

    Condition: New.

    Seller page

  • steeldives.com $169 (about £127), seen 2 Oct, in stock

    SD1975 coral-blue dial, 3-link bracelet

    Condition: New.

    Seller page

  • www.steeldives.com $169 (about £127), seen 2 Oct

    SD1975 blue

    Condition: New.

    Seller page
More from Steeldive4 more on Bewrist

Every Steeldive watch

Beside other Seiko Tuna homagesThis watch and 4 more of its look, to scale

Drawn to scale by listed case width.

All 5 on the look page

SourcesThe page this record was built from