Seiko Cal. 3840 - 764

The Seiko 3840-764 represents an important milestone in Seiko's 1986 lineup. Powered by the 3840 caliber with 18j jewels beating at 28,800 bph, it delivers a 69 hours power reserve. [seikata-wm-dbe302164a30]

Also known as: Helmet, Bellmatic

Specifications

Movement

Hand-Winding

Case Material

PVD Black

Case Width

35mm

Case Thickness

9.1mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Fixed

Water Resistance

180m

Dial Color

Blue Sunburst

Jewels

18j

Frequency

28,800 bph

Power Reserve

69 hours

Year

1986

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