Seiko Cal. 6635 - 991

This Hand-Winding model from 1971 features a 41mm Titanium case. It features a Blue Sunburst dial protected by a Mineral crystal and offers 90m of water resistance. [seikata-wm-e8224b8faeb5]

Also known as: Bellmatic, Navigator

Specifications

Movement

Hand-Winding

Case Material

Titanium

Case Width

41mm

Case Thickness

13.1mm

Lug Width

22mm

Crystal

Mineral

Bezel

Fixed

Water Resistance

90m

Dial Color

Blue Sunburst

Jewels

28j

Frequency

21,600 bph

Power Reserve

36 hours

Year

1971

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