What are the case specifications of the Seiko?

The Seiko features a 42.8mm diameter, 9.1mm thick, Steel case with a mineral glass crystal.

What is the water resistance of the Seiko?

The Seiko has a water resistance rating of 100m (swimming).

What movement does the Seiko use?

The Seiko is powered by a caliber 4T57.

Seiko SKS631

Steel

Ref. SKS631

Case size: 42.8mmMovement: 4T57

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Last updated 8 Oct 2026Suggest a correction

TECHNICAL SPECIFICATIONS

GENERAL

Gender

Men

CASE

Diameter

42.8mm

Thickness

9.1mm

Lug Width

20mm

Case Material

Steel

Water Resistance

100m

Crystal

Mineral Glass

MOVEMENT

Caliber

4T57

BRACELET/STRAP

Clasp Type

Fold Clasp

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QUICK FACTS

BRAND

Seiko

REFERENCE

SKS631

CALIBER

4T57

CASE MATERIAL

Steel

CRYSTAL

Mineral Glass

WATER RESISTANCE

100m (swimming)

GENDER

Men

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Last updated 8 Oct 2026Suggest a correction

FOR WATCH DEALERS

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Seiko SKS631

TECHNICAL SPECIFICATIONS

GENERAL

CASE

MOVEMENT

BRACELET/STRAP

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Other watches with the 4T57 calibre

SKS535

SKS539P2

SKS541

SKS543

SKS544

SKS632

SKS641

SKS646

QUICK FACTS

FOR WATCH DEALERS