Seiko Cal. 6637 - 928

The Seiko 6637-928 represents an important milestone in Seiko's 1977 lineup. Powered by the 6637 caliber with 22j jewels beating at 36,000 bph, it delivers a 56 hours power reserve. [seikata-wm-79f5d8b10364]

Also known as: Sumo

Specifications

Movement

Kinetic

Case Material

Hardlex-Coated Steel

Case Width

45mm

Case Thickness

10.9mm

Lug Width

22mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

140m

Dial Color

Burgundy

Jewels

22j

Frequency

36,000 bph

Power Reserve

56 hours

Year

1977

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