Seiko Cal. 4420 - 821

The Seiko 4420-821 represents an important milestone in Seiko's 1966 lineup. Powered by the 4420 caliber with 28j jewels beating at 28,800 bph, it delivers a 64 hours power reserve. [seikata-wm-efcb53ea9d47]

Also known as: Tuna, Crown

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

41mm

Case Thickness

9.4mm

Lug Width

18mm

Crystal

Hardlex

Bezel

Fixed

Water Resistance

90m

Dial Color

Burgundy

Jewels

28j

Frequency

28,800 bph

Power Reserve

64 hours

Year

1966

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