Seiko Cal. 6643 - 237

The Seiko 6643-237 represents an important milestone in Seiko's 1966 lineup. It features a Navy dial protected by a Sapphire crystal and offers 140m of water resistance. [seikata-wm-cd580bd5010a]

Also known as: Sportsmatic

Specifications

Movement

Hand-Winding

Case Material

PVD Black

Case Width

43mm

Case Thickness

8.3mm

Lug Width

18mm

Crystal

Sapphire

Bezel

Coin-Edge

Water Resistance

140m

Dial Color

Navy

Jewels

19j

Frequency

28,800 bph

Power Reserve

41 hours

Year

1966

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