Seiko Cal. 6638 - 787

This Hand-Winding model from 1978 features a 41mm Titanium case. It features a Green dial protected by a Mineral crystal and offers 120m of water resistance. [seikata-wm-6817440f195d]

Also known as: Sportsmatic

Specifications

Movement

Hand-Winding

Case Material

Titanium

Case Width

41mm

Case Thickness

9.3mm

Lug Width

20mm

Crystal

Mineral

Bezel

Inner Rotating

Water Resistance

120m

Dial Color

Green

Jewels

24j

Frequency

21,600 bph

Power Reserve

58 hours

Year

1978

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