Seiko Cal. 6631 - 857

The Seiko 6631-857 represents an important milestone in Seiko's 1978 lineup. It features a Green dial protected by a Sapphire crystal and offers 150m of water resistance. [seikata-wm-a896cda07687]

Also known as: Helmet

Specifications

Movement

Kinetic

Case Material

Two-Tone

Case Width

45mm

Case Thickness

9.6mm

Lug Width

19mm

Crystal

Sapphire

Bezel

Inner Rotating

Water Resistance

150m

Dial Color

Green

Jewels

31j

Frequency

36,000 bph

Power Reserve

69 hours

Year

1978

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