Seiko Cal. 4421 - 639

The Seiko 4421-639 represents an important milestone in Seiko's 1975 lineup. Powered by the 4421 caliber with 19j jewels beating at 28,800 bph, it delivers a 51 hours power reserve. [seikata-wm-b81e34d73e42]

Also known as: Sportsmatic

Specifications

Movement

Hand-Winding

Case Material

Hardlex-Coated Steel

Case Width

38mm

Case Thickness

12.1mm

Lug Width

19mm

Crystal

Mineral

Bezel

Fixed

Water Resistance

200m

Dial Color

Cream

Jewels

19j

Frequency

28,800 bph

Power Reserve

51 hours

Year

1975

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