Seiko Cal. 3816 - 931

This Spring Drive model from 1978 features a 40mm Hardlex-Coated Steel case. Powered by the 3816 caliber with 32j jewels beating at 28,800 bph, it delivers a 60 hours power reserve. [seikata-wm-2e1eef4f16a4]

Also known as: World Timer

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

40mm

Case Thickness

15.4mm

Lug Width

18mm

Crystal

Acrylic

Bezel

Coin-Edge

Water Resistance

110m

Dial Color

Silver

Jewels

32j

Frequency

28,800 bph

Power Reserve

60 hours

Year

1978

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