Seiko Cal. 6631 - 435

The Seiko 6631-435 represents an important milestone in Seiko's 1970 lineup. It features a Cream dial protected by a Hardlex crystal and offers 40m of water resistance. [seikata-wm-6024c4a2f95b]

Also known as: Tuna, Bullhead

Specifications

Movement

Automatic

Case Material

Two-Tone

Case Width

41mm

Case Thickness

14.0mm

Lug Width

18mm

Crystal

Hardlex

Bezel

Rotating

Water Resistance

40m

Dial Color

Cream

Jewels

36j

Frequency

36,000 bph

Power Reserve

52 hours

Year

1970

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