Seiko Cal. 6631 - 159

This Hand-Winding model from 1999 features a 42mm Titanium case. Powered by the 6631 caliber with 23j jewels beating at 36,000 bph, it delivers a 64 hours power reserve. [seikata-wm-574d85383ac0]

Also known as: Bullhead, Emperor

Specifications

Movement

Hand-Winding

Case Material

Titanium

Case Width

42mm

Case Thickness

13.7mm

Lug Width

22mm

Crystal

Mineral

Bezel

Rotating

Water Resistance

100m

Dial Color

Black

Jewels

23j

Frequency

36,000 bph

Power Reserve

64 hours

Year

1999

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