Seiko Cal. 5638 - 444

The Seiko 5638-444 represents an important milestone in Seiko's 1966 lineup. With its 18mm lug width and 10.3mm profile, it sits comfortably on most wrists. [seikata-wm-93fc1825cf17]

Also known as: Helmet, Rally

Specifications

Movement

Spring Drive

Case Material

PVD Black

Case Width

37mm

Case Thickness

10.3mm

Lug Width

18mm

Crystal

Sapphire

Bezel

Bidirectional

Water Resistance

30m

Dial Color

Navy

Jewels

24j

Frequency

36,000 bph

Power Reserve

57 hours

Year

1966

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