Seiko Cal. 5638 - 921

This Spring Drive model from 1978 features a 45mm Hardlex-Coated Steel case. It features a Navy dial protected by a Acrylic crystal and offers 120m of water resistance. [seikata-wm-e2330cf7ba0c]

Also known as: Tuna, Baby Tuna

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

45mm

Case Thickness

13.7mm

Lug Width

19mm

Crystal

Acrylic

Bezel

Bidirectional

Water Resistance

120m

Dial Color

Navy

Jewels

30j

Frequency

28,800 bph

Power Reserve

65 hours

Year

1978

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