Seiko Cal. 6620 - 643

Released in 1971, the Cal. 6620 with design code 643 was part of Seiko's domestic market collection. It features a Navy dial protected by a Hardlex crystal and offers 110m of water resistance. [seikata-wm-ea901dd090f9]

Also known as: Sumo

Specifications

Movement

Automatic

Case Material

Titanium

Case Width

44mm

Case Thickness

13.6mm

Lug Width

19mm

Crystal

Hardlex

Bezel

Coin-Edge

Water Resistance

110m

Dial Color

Navy

Jewels

20j

Frequency

28,800 bph

Power Reserve

62 hours

Year

1971

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