Seiko Cal. 6687 - 990

The Seiko 6687-990 represents an important milestone in Seiko's 1967 lineup. Powered by the 6687 caliber with 21j jewels beating at 21,600 bph, it delivers a 44 hours power reserve. [seikata-wm-424e83c5a505]

Also known as: Sumo

Specifications

Movement

Hand-Winding

Case Material

Stainless Steel

Case Width

36mm

Case Thickness

14.1mm

Lug Width

21mm

Crystal

Acrylic

Bezel

Rotating

Water Resistance

180m

Dial Color

Blue Sunburst

Jewels

21j

Frequency

21,600 bph

Power Reserve

44 hours

Year

1967

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