Seiko Cal. 3831 - 731

This Automatic model from 1979 features a 42mm Hardlex-Coated Steel case. Powered by the 3831 caliber with 32j jewels beating at 21,600 bph, it delivers a 53 hours power reserve. [seikata-wm-70d7208cca64]

Also known as: UFO, Baby Tuna

Specifications

Movement

Automatic

Case Material

Hardlex-Coated Steel

Case Width

42mm

Case Thickness

10.6mm

Lug Width

19mm

Crystal

Hardlex

Bezel

Bidirectional

Water Resistance

180m

Dial Color

Silver

Jewels

32j

Frequency

21,600 bph

Power Reserve

53 hours

Year

1979

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