Seiko Cal. 6645 - 447

This Spring Drive model from 1981 features a 37mm Two-Tone case. Powered by the 6645 caliber with 18j jewels beating at 28,800 bph, it delivers a 39 hours power reserve. [seikata-wm-5ef8b95dc12d]

Also known as: World Timer, Crown

Specifications

Movement

Spring Drive

Case Material

Two-Tone

Case Width

37mm

Case Thickness

9.5mm

Lug Width

19mm

Crystal

Mineral

Bezel

Rotating

Water Resistance

150m

Dial Color

Burgundy

Jewels

18j

Frequency

28,800 bph

Power Reserve

39 hours

Year

1981

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