Seiko Cal. 6687 - 731

The Seiko 6687-731 represents an important milestone in Seiko's 1985 lineup. Powered by the 6687 caliber with 17j jewels beating at 28,800 bph, it delivers a 69 hours power reserve. [seikata-wm-44a75a7f87bc]

Also known as: Tuna

Specifications

Movement

Automatic

Case Material

Titanium

Case Width

45mm

Case Thickness

12.8mm

Lug Width

21mm

Crystal

Acrylic

Bezel

Coin-Edge

Water Resistance

50m

Dial Color

Champagne

Jewels

17j

Frequency

28,800 bph

Power Reserve

69 hours

Year

1985

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