Seiko Cal. 6631 - 291

Released in 1974, the Cal. 6631 with design code 291 was part of Seiko's domestic market collection. It features a Green dial protected by a Sapphire crystal and offers 140m of water resistance. [seikata-wm-2f1c52afd2fb]

Also known as: Turtle, Golden Tuna

Specifications

Movement

Hand-Winding

Case Material

Titanium

Case Width

35mm

Case Thickness

12.8mm

Lug Width

21mm

Crystal

Sapphire

Bezel

Coin-Edge

Water Resistance

140m

Dial Color

Green

Jewels

22j

Frequency

36,000 bph

Power Reserve

69 hours

Year

1974

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