Seiko Cal. 6661 - 644

The Seiko 6661-644 represents an important milestone in Seiko's 1970 lineup. Powered by the 6661 caliber with 36j jewels beating at 36,000 bph, it delivers a 65 hours power reserve. [seikata-wm-157541715071]

Also known as: Bullhead

Specifications

Movement

Spring Drive

Case Material

Two-Tone

Case Width

36mm

Case Thickness

10.5mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

100m

Dial Color

White

Jewels

36j

Frequency

36,000 bph

Power Reserve

65 hours

Year

1970

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