Seiko Cal. 6638 - 221

The Seiko 6638-221 represents an important milestone in Seiko's 1971 lineup. Powered by the 6638 caliber with 31j jewels beating at 36,000 bph, it delivers a 55 hours power reserve. [seikata-wm-be387c458491]

Also known as: Silverwave

Specifications

Movement

Automatic

Case Material

Gold-Plated

Case Width

43mm

Case Thickness

12.5mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Coin-Edge

Water Resistance

70m

Dial Color

Burgundy

Jewels

31j

Frequency

36,000 bph

Power Reserve

55 hours

Year

1971

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