Seiko Cal. 5640 - 901

The Seiko 5640-901 represents an important milestone in Seiko's 1972 lineup. Powered by the 5640 caliber with 22j jewels beating at 36,000 bph, it delivers a 68 hours power reserve. [seikata-wm-5bcb504a5248]

Also known as: Monster, Sea Horse

Specifications

Movement

Automatic

Case Material

Stainless Steel

Case Width

43mm

Case Thickness

13.0mm

Lug Width

20mm

Crystal

Sapphire

Bezel

Inner Rotating

Water Resistance

160m

Dial Color

Burgundy

Jewels

22j

Frequency

36,000 bph

Power Reserve

68 hours

Year

1972

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