Seiko Cal. 6660 - 991

The Seiko 6660-991 represents an important milestone in Seiko's 1969 lineup. The Bidirectional bezel and 45mm case give it a distinctive presence on the wrist. [seikata-wm-eb8acbda76b7]

Specifications

Movement

Solar

Case Material

PVD Black

Case Width

45mm

Case Thickness

12.3mm

Lug Width

18mm

Crystal

Sapphire

Bezel

Bidirectional

Water Resistance

110m

Dial Color

Green

Jewels

36j

Frequency

21,600 bph

Power Reserve

72 hours

Year

1969

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