Seiko Cal. 6647 - 581

The Seiko 6647-581 represents an important milestone in Seiko's 1991 lineup. Powered by the 6647 caliber with 20j jewels beating at 21,600 bph, it delivers a 50 hours power reserve. [seikata-wm-8160e23f92c0]

Also known as: Bullhead, Baby Tuna

Specifications

Movement

Automatic

Case Material

Titanium

Case Width

37mm

Case Thickness

9.6mm

Lug Width

18mm

Crystal

Acrylic

Bezel

Fixed

Water Resistance

150m

Dial Color

Navy

Jewels

20j

Frequency

21,600 bph

Power Reserve

50 hours

Year

1991

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