Seiko Cal. 6640 - 440

The Seiko 6640-440 represents an important milestone in Seiko's 1990 lineup. Powered by the 6640 caliber with 20j jewels beating at 28,800 bph, it delivers a 65 hours power reserve. [seikata-wm-6bd5ba050d4c]

Also known as: Panda, Helmet

Specifications

Movement

Automatic

Case Material

Hardlex-Coated Steel

Case Width

44mm

Case Thickness

9.3mm

Lug Width

21mm

Crystal

Mineral

Bezel

Bidirectional

Water Resistance

40m

Dial Color

Burgundy

Jewels

20j

Frequency

28,800 bph

Power Reserve

65 hours

Year

1990

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