Seiko Cal. 6640 - 840

Released in 1995, the Cal. 6640 with design code 840 was part of Seiko's domestic market collection. The Rotating bezel and 36mm case give it a distinctive presence on the wrist. [seikata-wm-bca17da557da]

Also known as: Tuna, Crown

Specifications

Movement

Spring Drive

Case Material

Gold-Plated

Case Width

36mm

Case Thickness

14.2mm

Lug Width

20mm

Crystal

Sapphire

Bezel

Rotating

Water Resistance

80m

Dial Color

White

Jewels

30j

Frequency

21,600 bph

Power Reserve

45 hours

Year

1995

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