Seiko Cal. 6640 - 380

The 6640-380 is a sought-after Automatic piece from Seiko's golden era. It features a Navy dial protected by a Hardlex crystal and offers 170m of water resistance. [seikata-wm-124bb7084b1f]

Also known as: Monster, Arnie

Specifications

Movement

Automatic

Case Material

Hardlex-Coated Steel

Case Width

44mm

Case Thickness

14.1mm

Lug Width

19mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

170m

Dial Color

Navy

Jewels

23j

Frequency

36,000 bph

Power Reserve

64 hours

Year

1978

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