Seiko Cal. 6640 - 637

This Hand-Winding model from 1990 features a 46mm Two-Tone case. It features a Black dial protected by a Acrylic crystal and offers 40m of water resistance. [seikata-wm-1eb4e4c780db]

Also known as: Turtle, Shogun

Specifications

Movement

Hand-Winding

Case Material

Two-Tone

Case Width

46mm

Case Thickness

14.4mm

Lug Width

20mm

Crystal

Acrylic

Bezel

Rotating

Water Resistance

40m

Dial Color

Black

Jewels

27j

Frequency

21,600 bph

Power Reserve

40 hours

Year

1990

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