Seiko Cal. 6638 - 647

The Seiko 6638-647 represents an important milestone in Seiko's 1973 lineup. Powered by the 6638 caliber with 23j jewels beating at 21,600 bph, it delivers a 43 hours power reserve. [seikata-wm-9dacef9bf484]

Also known as: Helmet

Specifications

Movement

Solar

Case Material

Two-Tone

Case Width

34mm

Case Thickness

14.2mm

Lug Width

21mm

Crystal

Mineral

Bezel

Rotating

Water Resistance

80m

Dial Color

Champagne

Jewels

23j

Frequency

21,600 bph

Power Reserve

43 hours

Year

1973

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