Seiko Cal. 6643 - 622

Released in 1975, the Cal. 6643 with design code 622 was part of Seiko's domestic market collection. It features a Black dial protected by a Acrylic crystal and offers 50m of water resistance. [seikata-wm-d1d9cdc97aac]

Also known as: Helmet

Specifications

Movement

Hand-Winding

Case Material

PVD Black

Case Width

39mm

Case Thickness

11.3mm

Lug Width

21mm

Crystal

Acrylic

Bezel

Bidirectional

Water Resistance

50m

Dial Color

Black

Jewels

28j

Frequency

21,600 bph

Power Reserve

60 hours

Year

1975

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