Seiko Cal. 6690 - 657

The Seiko 6690-657 represents an important milestone in Seiko's 1985 lineup. Powered by the 6690 caliber with 24j jewels beating at 21,600 bph, it delivers a 51 hours power reserve. [seikata-wm-44cec9f900a0]

Also known as: Helmet

Specifications

Movement

Automatic

Case Material

Hardlex-Coated Steel

Case Width

44mm

Case Thickness

12.8mm

Lug Width

18mm

Crystal

Acrylic

Bezel

Bidirectional

Water Resistance

120m

Dial Color

Navy

Jewels

24j

Frequency

21,600 bph

Power Reserve

51 hours

Year

1985

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