Seiko Cal. 6638 - 916

This Automatic model from 1968 features a 38mm Titanium case. Powered by the 6638 caliber with 23j jewels beating at 28,800 bph, it delivers a 72 hours power reserve. [seikata-wm-680a9fdf1e4f]

Also known as: Bullhead

Specifications

Movement

Automatic

Case Material

Titanium

Case Width

38mm

Case Thickness

13.3mm

Lug Width

22mm

Crystal

Sapphire

Bezel

Rotating

Water Resistance

50m

Dial Color

Burgundy

Jewels

23j

Frequency

28,800 bph

Power Reserve

72 hours

Year

1968

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