Seiko Cal. 3840 - 720

The Seiko 3840-720 represents an important milestone in Seiko's 1983 lineup. It features a Burgundy dial protected by a Hardlex crystal and offers 180m of water resistance. [seikata-wm-1acc32fc4451]

Also known as: Monster, Tuna

Specifications

Movement

Spring Drive

Case Material

Two-Tone

Case Width

39mm

Case Thickness

9.3mm

Lug Width

22mm

Crystal

Hardlex

Bezel

Rotating

Water Resistance

180m

Dial Color

Burgundy

Jewels

33j

Frequency

36,000 bph

Power Reserve

36 hours

Year

1983

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