Seiko Cal. 6640 - 728

This Automatic model from 1994 features a 37mm Gold-Plated case. Powered by the 6640 caliber with 35j jewels beating at 21,600 bph, it delivers a 45 hours power reserve. [seikata-wm-4ea004db6dbe]

Also known as: Helmet, Golden Tuna

Specifications

Movement

Automatic

Case Material

Gold-Plated

Case Width

37mm

Case Thickness

9.6mm

Lug Width

19mm

Crystal

Sapphire

Bezel

Fixed

Water Resistance

160m

Dial Color

Green

Jewels

35j

Frequency

21,600 bph

Power Reserve

45 hours

Year

1994

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