Seiko Cal. 6638 - 766

The Seiko 6638-766 represents an important milestone in Seiko's 1985 lineup. Powered by the 6638 caliber with 25j jewels beating at 28,800 bph, it delivers a 52 hours power reserve. [seikata-wm-66b43dc7513f]

Also known as: Helmet

Specifications

Movement

Quartz

Case Material

PVD Black

Case Width

38mm

Case Thickness

9.9mm

Lug Width

22mm

Crystal

Sapphire

Bezel

Fixed

Water Resistance

90m

Dial Color

Burgundy

Jewels

25j

Frequency

28,800 bph

Power Reserve

52 hours

Year

1985

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