Seiko Cal. 6643 - 778

The Seiko 6643-778 represents an important milestone in Seiko's 1977 lineup. It features a White dial protected by a Sapphire crystal and offers 30m of water resistance. [seikata-wm-e91e1857048d]

Also known as: Bellmatic, Baby Tuna

Specifications

Movement

Spring Drive

Case Material

Stainless Steel

Case Width

35mm

Case Thickness

11.4mm

Lug Width

19mm

Crystal

Sapphire

Bezel

Fixed

Water Resistance

30m

Dial Color

White

Jewels

34j

Frequency

28,800 bph

Power Reserve

44 hours

Year

1977

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