Seiko Cal. 6639 - 881

This Hand-Winding model from 1981 features a 45mm Titanium case. Powered by the 6639 caliber with 21j jewels beating at 28,800 bph, it delivers a 50 hours power reserve. [seikata-wm-43020f99716e]

Also known as: Sumo, Bullhead

Specifications

Movement

Hand-Winding

Case Material

Titanium

Case Width

45mm

Case Thickness

13.5mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Bidirectional

Water Resistance

60m

Dial Color

Black

Jewels

21j

Frequency

28,800 bph

Power Reserve

50 hours

Year

1981

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