What are the case specifications of the Seiko King Seiko KSK?

The Seiko King Seiko KSK features a 39mm diameter, 11.9mm thick, Steel case with a sapphire crystal crystal.

What is the water resistance of the Seiko King Seiko KSK?

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

What movement does the Seiko King Seiko KSK use?

The Seiko King Seiko KSK is powered by a Automatic, caliber 6R55, 72h power reserve.

Seiko King Seiko KSK

AutomaticSteel

Ref. SPB371J1

Collection: King SeikoCase size: 39mmMovement: 6R55

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Last updated 8 Oct 2026Suggest a correction

TECHNICAL SPECIFICATIONS

GENERAL

Gender

Men

CASE

Diameter

39mm

Thickness

11.9mm

Lug to Lug

46.1mm

Lug Width

19mm

Case Material

Steel

Water Resistance

100m

Crystal

Sapphire Crystal

MOVEMENT

Movement Type

Automatic

Caliber

6R55

Power Reserve

72h

Frequency

21,600 vph (3 Hz)

Jewels

24 jewels

BRACELET/STRAP

Clasp Type

Fold Clasp

HBC006J1

AutomaticSteel

QUICK FACTS

BRAND

Seiko

REFERENCE

SPB371J1

COLLECTION

King Seiko

MOVEMENT

Automatic

CALIBER

6R55

CASE MATERIAL

Steel

CRYSTAL

Sapphire Crystal

WATER RESISTANCE

100m (swimming)

GENDER

Men

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Last updated 8 Oct 2026Suggest a correction

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Seiko King Seiko KSK

TECHNICAL SPECIFICATIONS

GENERAL

CASE

MOVEMENT

BRACELET/STRAP

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