Seiko Cal. 5631 - 723

This Hand-Winding model from 1965 features a 39mm PVD Black case. It features a Burgundy dial protected by a Mineral crystal and offers 160m of water resistance. [seikata-wm-b40f923dad09]

Also known as: Monster, Baby Tuna

Specifications

Movement

Hand-Winding

Case Material

PVD Black

Case Width

39mm

Case Thickness

9.2mm

Lug Width

19mm

Crystal

Mineral

Bezel

Coin-Edge

Water Resistance

160m

Dial Color

Burgundy

Jewels

21j

Frequency

21,600 bph

Power Reserve

38 hours

Year

1965

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