SeikoProspex 1965 Diver

Seiko Prospex dive watch on a bracelet
Seiko Prospex SPB143 on the wrist

In the photo: the exact model. A licensed sample image; the official one will replace it. Header: a Seiko Prospex.

Seiko Prospex 1965 Diver€1,240–1,340
Seiko · Ref. SPB143J1 · Dive · Japan

Indicative price band. The exact price is on Amazon.

See price on Amazon
  • Seiko’s first diver, from 1965, reissued at 40.5 mm with sapphire, 200 m and the 70-hour 6R35.
  • 6R35 movement with 70 h of power reserve at 21,600 bph.
  • Hacking seconds and hand winding.
  • Sapphire crystal and 200 m water resistance.
  • 40.5 mm diameter, 13.2 mm thick and 47.6 mm lug-to-lug.

Affiliate link: if you buy, Amazon pays Calibrario a commission and you pay the same. Availability on Amazon.es checked on 21 October 2026.

In figures

70 hPower reserve
40.5mm diameter
13.2mm thick
47.6mm lug-to-lug
200 mWater resistance
SapphireCrystal

Will it fit your wrist?

Move the slider to your wrist circumference. Seen from above, your wrist is roughly a third of that wide; if the lug-to-lug is wider, the watch overhangs.

Scale drawing of the Seiko Prospex 1965 Diver: 40.5 mm diameter, 47.6 mm lug-to-lug and 13.2 mm thickØ 40.5 mm47.6 mm lug-to-lug13.2 mm

With a 17 cm circumference, your wrist is about 56 mm wide.

Prospex 1965 Diver40.5 mmDiver43.6 mmPromaster Fujitsubo41 mm

Specifications

Movement

Movement6R35
Movement makerSeiko
Power reserve70 h
Beat rate21,600 bph
Hacking secondsYes
Hand windingYes

Case and crystal

Diameter40.5 mm
Thickness13.2 mm
Lug-to-lug47.6 mm
CaseSteel
CrystalSapphire
Water resistance200 m
Rotating bezelYes, unidirectional
Display casebackNo

Strap and dial

Lug widthIntegrated
Strap or braceletSteel bracelet
DialGrey
ComplicationsDate

Buying

Indicative price band€1,240–1,340
StyleDive
Brand originJapan

Data checked against the manufacturer’s official website on 21 October 2026. A dash means the manufacturer does not publish that figure.

Sources: seikowatches.com (archived copy), seikowatches.com

The movement

Seiko’s next step up: the same idea as the 4R, but with about 70 hours of reserve.

All about the Seiko 6R35

Against its rivals

Seiko Prospex SPB143 on the wrist
Seiko Prospex 1965 Diver
6R35, 70 h, sapphire, 200 m, 40.5 mm
€1,240–1,340
Scale drawing of the Orient Star Diver: 43.6 mm diameter, 51.1 mm lug-to-lug and 14 mm thick
Orient Star Diver
F6N47, 50 h, sapphire, 200 m, 43.6 mm
€700–760
Scale drawing of the Citizen Promaster Fujitsubo: 41 mm diameter, 46 mm lug-to-lug and 12 mm thick
Citizen Promaster Fujitsubo
9051, 42 h, sapphire, 200 m, 41 mm
€560–620
Figure Seiko Prospex 1965 DiverOrient Star DiverCitizen Promaster Fujitsubo
Indicative price band€1,240–1,340€700–760€560–620
Movement6R35F6N479051
Power reserve70 h50 h42 h
Beat rate21,600 bph21,600 bph28,800 bph
CrystalSapphireSapphireSapphire
Water resistance200 m200 m200 m
Diameter40.5 mm43.6 mm41 mm
Thickness13.2 mm14 mm—
Lug-to-lug47.6 mm51.1 mm—
Hacking secondsYesYesYes
Hand windingYesYesYes
Rotating bezelYesYesYes
Strap or braceletSteel braceletSteel braceletTitanium bracelet
Brand originJapanJapanJapan
See price on AmazonSee specsSee price on AmazonSee specsSee price on AmazonSee specs

Watches of the same style with the nearest price band. In red, the best figure in each row.

Making sense of the specs

Caseback of an automatic watch showing the rotor Power reserveHow long it keeps running off the wrist, and why 80 hours changes daily life.Read the guide Dial of a Seiko chronograph, close up Sapphire, Hardlex or mineralWhich crystal scratches, which chips and which is worth it.Read the guide

Frequently asked questions

Which movement does the Seiko Prospex 1965 Diver use?

The 6R35, from the Seiko 6R35 family, made by Seiko. It gives 70 h of power reserve at 21,600 bph.

Does it have hacking seconds and hand winding?

The seconds hand stops when you pull the crown, and it can be wound by hand by turning it.

Can you swim or dive with it?

It is water resistant to 200 m: fine for swimming and diving. For scuba diving, check that the model meets ISO 6425.

What size wrist does it suit?

With a 47.6 mm lug-to-lug, it suits wrists from about 15.5 cm in circumference. Below that, the lugs reach the edge. You can work it out with your own measurement on this page.