Seiko Cal. 6687 - 935

This Spring Drive model from 1977 features a 37mm Hardlex-Coated Steel case. It features a Burgundy dial protected by a Sapphire crystal and offers 180m of water resistance. [seikata-wm-57a2798d1584]

Also known as: Sumo

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

37mm

Case Thickness

12.5mm

Lug Width

19mm

Crystal

Sapphire

Bezel

Bidirectional

Water Resistance

180m

Dial Color

Burgundy

Jewels

23j

Frequency

21,600 bph

Power Reserve

53 hours

Year

1977

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