Seiko Cal. 6637 - 896

This Automatic model from 1977 features a 43mm Hardlex-Coated Steel case. Powered by the 6637 caliber with 31j jewels beating at 36,000 bph, it delivers a 52 hours power reserve. [seikata-wm-0b8c0178c91a]

Also known as: Tuna, World Timer

Specifications

Movement

Automatic

Case Material

Hardlex-Coated Steel

Case Width

43mm

Case Thickness

14.2mm

Lug Width

22mm

Crystal

Mineral

Bezel

Rotating

Water Resistance

200m

Dial Color

Black

Jewels

31j

Frequency

36,000 bph

Power Reserve

52 hours

Year

1977

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