Seiko Cal. 4421 - 657

Released in 1981, the Cal. 4421 with design code 657 was part of Seiko's domestic market collection. It features a White dial protected by a Acrylic crystal and offers 170m of water resistance. [seikata-wm-103cc612df42]

Also known as: Helmet, Silverwave

Specifications

Movement

Quartz

Case Material

Gold-Plated

Case Width

45mm

Case Thickness

8.9mm

Lug Width

18mm

Crystal

Acrylic

Bezel

Fixed

Water Resistance

170m

Dial Color

White

Jewels

23j

Frequency

36,000 bph

Power Reserve

60 hours

Year

1981

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