Seiko Cal. 6661 - 640

The Seiko 6661-640 represents an important milestone in Seiko's 1985 lineup. Powered by the 6661 caliber with 21j jewels beating at 36,000 bph, it delivers a 54 hours power reserve. [seikata-wm-a36c4bb6f97c]

Also known as: Sumo

Specifications

Movement

Solar

Case Material

Titanium

Case Width

45mm

Case Thickness

9.9mm

Lug Width

22mm

Crystal

Mineral

Bezel

Fixed

Water Resistance

200m

Dial Color

Silver

Jewels

21j

Frequency

36,000 bph

Power Reserve

54 hours

Year

1985

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