Seiko Cal. 6638 - 228

The Seiko 6638-228 represents an important milestone in Seiko's 1968 lineup. Powered by the 6638 caliber with 22j jewels beating at 36,000 bph, it delivers a 63 hours power reserve. [seikata-wm-aa39b2a4bea9]

Also known as: Bullhead

Specifications

Movement

Automatic

Case Material

Titanium

Case Width

37mm

Case Thickness

12.1mm

Lug Width

22mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

50m

Dial Color

Cream

Jewels

22j

Frequency

36,000 bph

Power Reserve

63 hours

Year

1968

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