Seiko Cal. 6645 - 720

The 6645-720 is a sought-after Kinetic piece from Seiko's golden era. Powered by the 6645 caliber with 21j jewels beating at 36,000 bph, it delivers a 43 hours power reserve. [seikata-wm-7f68522688de]

Also known as: Tuna, Crown

Specifications

Movement

Kinetic

Case Material

Two-Tone

Case Width

41mm

Case Thickness

14.3mm

Lug Width

22mm

Crystal

Hardlex

Bezel

Bidirectional

Water Resistance

180m

Dial Color

White

Jewels

21j

Frequency

36,000 bph

Power Reserve

43 hours

Year

1972

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