Seiko Cal. 6631 - 181

Released in 1982, the Cal. 6631 with design code 181 was part of Seiko's domestic market collection. It features a Cream dial protected by a Hardlex crystal and offers 90m of water resistance. [seikata-wm-0cde2bcdc8be]

Also known as: Bullhead, Golden Tuna

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

36mm

Case Thickness

11.8mm

Lug Width

18mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

90m

Dial Color

Cream

Jewels

28j

Frequency

28,800 bph

Power Reserve

64 hours

Year

1982

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