Seiko Cal. 5640 - 991

This Spring Drive model from 1968 features a 41mm Two-Tone case. Powered by the 5640 caliber with 33j jewels beating at 36,000 bph, it delivers a 50 hours power reserve. [seikata-wm-dee354da7e57]

Specifications

Movement

Spring Drive

Case Material

Two-Tone

Case Width

41mm

Case Thickness

12.0mm

Lug Width

18mm

Crystal

Mineral

Bezel

Coin-Edge

Water Resistance

60m

Dial Color

Burgundy

Jewels

33j

Frequency

36,000 bph

Power Reserve

50 hours

Year

1968

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