Seiko Cal. 6638 - 515

The Seiko 6638-515 represents an important milestone in Seiko's 1970 lineup. Powered by the 6638 caliber with 31j jewels beating at 21,600 bph, it delivers a 71 hours power reserve. [seikata-wm-1e865bc43a8a]

Also known as: Bullhead, Emperor

Specifications

Movement

Kinetic

Case Material

PVD Black

Case Width

34mm

Case Thickness

11.4mm

Lug Width

19mm

Crystal

Mineral

Bezel

Fixed

Water Resistance

130m

Dial Color

Burgundy

Jewels

31j

Frequency

21,600 bph

Power Reserve

71 hours

Year

1970

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