Seiko Cal. 6640 - 461

The Seiko 6640-461 represents an important milestone in Seiko's 1980 lineup. The Inner Rotating bezel and 44mm case give it a distinctive presence on the wrist. [seikata-wm-d871c2af3af9]

Also known as: Turtle, Rally

Specifications

Movement

Spring Drive

Case Material

Two-Tone

Case Width

44mm

Case Thickness

13.4mm

Lug Width

22mm

Crystal

Mineral

Bezel

Inner Rotating

Water Resistance

170m

Dial Color

Black

Jewels

17j

Frequency

36,000 bph

Power Reserve

40 hours

Year

1980

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