Seiko Cal. 6691 - 657

The Seiko 6691-657 represents an important milestone in Seiko's 1986 lineup. It features a Cream dial protected by a Hardlex crystal and offers 120m of water resistance. [seikata-wm-7e719e3257ab]

Also known as: Helmet, Bellmatic

Specifications

Movement

Spring Drive

Case Material

Titanium

Case Width

45mm

Case Thickness

14.9mm

Lug Width

19mm

Crystal

Hardlex

Bezel

Fixed

Water Resistance

120m

Dial Color

Cream

Jewels

25j

Frequency

36,000 bph

Power Reserve

68 hours

Year

1986

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