Seiko Cal. 6657 - 631

This Automatic model from 1973 features a 41mm Stainless Steel case. It features a Blue Sunburst dial protected by a Hardlex crystal and offers 80m of water resistance. [seikata-wm-4b7f77e853d0]

Also known as: Bullhead

Specifications

Movement

Automatic

Case Material

Stainless Steel

Case Width

41mm

Case Thickness

8.4mm

Lug Width

22mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

80m

Dial Color

Blue Sunburst

Jewels

18j

Frequency

28,800 bph

Power Reserve

38 hours

Year

1973

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