Seiko Cal. 6621 - 664

This Spring Drive model from 1978 features a 40mm Hardlex-Coated Steel case. It features a Navy dial protected by a Sapphire crystal and offers 90m of water resistance. [seikata-wm-d2f8fc264d18]

Also known as: Monster, Bellmatic

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

40mm

Case Thickness

9.1mm

Lug Width

21mm

Crystal

Sapphire

Bezel

Fixed

Water Resistance

90m

Dial Color

Navy

Jewels

34j

Frequency

21,600 bph

Power Reserve

71 hours

Year

1978

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