Seiko Cal. 5687 - 644

The 5687-644 is a sought-after Spring Drive piece from Seiko's golden era. It features a Navy dial protected by a Acrylic crystal and offers 40m of water resistance. [seikata-wm-494d414b9626]

Also known as: Bullhead, Baby Tuna

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

41mm

Case Thickness

10.2mm

Lug Width

21mm

Crystal

Acrylic

Bezel

Bidirectional

Water Resistance

40m

Dial Color

Navy

Jewels

34j

Frequency

28,800 bph

Power Reserve

50 hours

Year

1979

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