Seiko Cal. 6689 - 721

The Seiko 6689-721 represents an important milestone in Seiko's 1971 lineup. It features a Blue Sunburst dial protected by a Sapphire crystal and offers 140m of water resistance. [seikata-wm-48f9f6b5ee05]

Also known as: Bullhead, Flighty

Specifications

Movement

Hand-Winding

Case Material

Gold-Plated

Case Width

35mm

Case Thickness

9.7mm

Lug Width

22mm

Crystal

Sapphire

Bezel

Coin-Edge

Water Resistance

140m

Dial Color

Blue Sunburst

Jewels

25j

Frequency

28,800 bph

Power Reserve

45 hours

Year

1971

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