Seiko Cal. 6638 - 787

The Seiko 6638-787 represents an important milestone in Seiko's 1974 lineup. It features a Blue Sunburst dial protected by a Sapphire crystal and offers 100m of water resistance. [seikata-wm-eaf70eeb8572]

Also known as: Monster, Sportsmatic

Specifications

Movement

Solar

Case Material

Titanium

Case Width

45mm

Case Thickness

12.0mm

Lug Width

21mm

Crystal

Sapphire

Bezel

Inner Rotating

Water Resistance

100m

Dial Color

Blue Sunburst

Jewels

24j

Frequency

21,600 bph

Power Reserve

64 hours

Year

1974

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