Seiko Cal. 5640 - 442

The Seiko 5640-442 represents an important milestone in Seiko's 1970 lineup. It features a Blue Sunburst dial protected by a Sapphire crystal and offers 140m of water resistance. [seikata-wm-c06ea18341da]

Also known as: Samurai

Specifications

Movement

Hand-Winding

Case Material

PVD Black

Case Width

39mm

Case Thickness

14.3mm

Lug Width

20mm

Crystal

Sapphire

Bezel

Inner Rotating

Water Resistance

140m

Dial Color

Blue Sunburst

Jewels

35j

Frequency

36,000 bph

Power Reserve

55 hours

Year

1970

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