Seiko Cal. 6644 - 781

This Hand-Winding model from 1981 features a 37mm Titanium case. Powered by the 6644 caliber with 22j jewels beating at 36,000 bph, it delivers a 68 hours power reserve. [seikata-wm-df73c8baf4bc]

Also known as: Sumo, Sea Horse

Specifications

Movement

Hand-Winding

Case Material

Titanium

Case Width

37mm

Case Thickness

12.1mm

Lug Width

18mm

Crystal

Acrylic

Bezel

Fixed

Water Resistance

40m

Dial Color

Burgundy

Jewels

22j

Frequency

36,000 bph

Power Reserve

68 hours

Year

1981

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