Seiko Cal. 6638 - 646

The Seiko 6638-646 represents an important milestone in Seiko's 1977 lineup. It features a Cream dial protected by a Acrylic crystal and offers 50m of water resistance. [seikata-wm-d5d3b7271a30]

Specifications

Movement

Spring Drive

Case Material

Titanium

Case Width

42mm

Case Thickness

13.6mm

Lug Width

21mm

Crystal

Acrylic

Bezel

Rotating

Water Resistance

50m

Dial Color

Cream

Jewels

36j

Frequency

21,600 bph

Power Reserve

66 hours

Year

1977

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