Seiko Cal. 6637 - 344

This Hand-Winding model from 1978 features a 38mm Stainless Steel case. It features a Burgundy dial protected by a Sapphire crystal and offers 100m of water resistance. [seikata-wm-c4491767319b]

Also known as: Sumo, World Timer

Specifications

Movement

Hand-Winding

Case Material

Stainless Steel

Case Width

38mm

Case Thickness

13.2mm

Lug Width

22mm

Crystal

Sapphire

Bezel

Fixed

Water Resistance

100m

Dial Color

Burgundy

Jewels

30j

Frequency

21,600 bph

Power Reserve

65 hours

Year

1978

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