Seiko Cal. 6631 - 904

Released in 1966, the Cal. 6631 with design code 904 was part of Seiko's domestic market collection. It features a Navy dial protected by a Acrylic crystal and offers 200m of water resistance. [seikata-wm-5c90bb8936fa]

Also known as: Shogun, Sea Horse

Specifications

Movement

Automatic

Case Material

Two-Tone

Case Width

37mm

Case Thickness

14.0mm

Lug Width

22mm

Crystal

Acrylic

Bezel

Bidirectional

Water Resistance

200m

Dial Color

Navy

Jewels

25j

Frequency

21,600 bph

Power Reserve

36 hours

Year

1966

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