Seiko Cal. 6637 - 520

This Quartz model from 1975 features a 45mm PVD Black case. The Bidirectional bezel and 45mm case give it a distinctive presence on the wrist. [seikata-wm-7cb88395491f]

Also known as: Bullhead

Specifications

Movement

Quartz

Case Material

PVD Black

Case Width

45mm

Case Thickness

11.9mm

Lug Width

22mm

Crystal

Acrylic

Bezel

Bidirectional

Water Resistance

200m

Dial Color

Navy

Jewels

32j

Frequency

21,600 bph

Power Reserve

72 hours

Year

1975

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