Seiko Cal. 6640 - 725

The Seiko 6640-725 represents an important milestone in Seiko's 1996 lineup. The Coin-Edge bezel and 36mm case give it a distinctive presence on the wrist. [seikata-wm-ab1afc0290da]

Also known as: Helmet, Arnie

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

36mm

Case Thickness

13.0mm

Lug Width

18mm

Crystal

Sapphire

Bezel

Coin-Edge

Water Resistance

130m

Dial Color

Silver

Jewels

31j

Frequency

28,800 bph

Power Reserve

72 hours

Year

1996

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