Seiko Cal. 5631 - 899

The Seiko 5631-899 represents an important milestone in Seiko's 1966 lineup. It features a Silver dial protected by a Mineral crystal and offers 120m of water resistance. [seikata-wm-b51153292ff2]

Also known as: Sportsmatic, Baby Tuna

Specifications

Movement

Solar

Case Material

Titanium

Case Width

34mm

Case Thickness

10.2mm

Lug Width

21mm

Crystal

Mineral

Bezel

Inner Rotating

Water Resistance

120m

Dial Color

Silver

Jewels

35j

Frequency

21,600 bph

Power Reserve

59 hours

Year

1966

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