Seiko Cal. 6637 - 645

This Hand-Winding model from 1988 features a 38mm PVD Black case. It features a White dial protected by a Sapphire crystal and offers 150m of water resistance. [seikata-wm-6bdddff1e4c4]

Also known as: Helmet, Flighty

Specifications

Movement

Hand-Winding

Case Material

PVD Black

Case Width

38mm

Case Thickness

11.6mm

Lug Width

20mm

Crystal

Sapphire

Bezel

Inner Rotating

Water Resistance

150m

Dial Color

White

Jewels

21j

Frequency

36,000 bph

Power Reserve

72 hours

Year

1988

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