Seiko Cal. 4421 - 307

This Spring Drive model from 1978 features a 42mm Two-Tone case. Powered by the 4421 caliber with 22j jewels beating at 36,000 bph, it delivers a 71 hours power reserve. [seikata-wm-9efbc749251a]

Also known as: World Timer, Navigator

Specifications

Movement

Spring Drive

Case Material

Two-Tone

Case Width

42mm

Case Thickness

13.7mm

Lug Width

20mm

Crystal

Mineral

Bezel

Coin-Edge

Water Resistance

200m

Dial Color

White

Jewels

22j

Frequency

36,000 bph

Power Reserve

71 hours

Year

1978

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