Seiko Cal. 6640 - 271

The 6640-271 is a sought-after Kinetic piece from Seiko's golden era. Powered by the 6640 caliber with 23j jewels beating at 28,800 bph, it delivers a 66 hours power reserve. [seikata-wm-b2eafa9bcedb]

Also known as: Sumo, World Timer

Specifications

Movement

Kinetic

Case Material

Two-Tone

Case Width

35mm

Case Thickness

9.2mm

Lug Width

18mm

Crystal

Sapphire

Bezel

Fixed

Water Resistance

150m

Dial Color

Green

Jewels

23j

Frequency

28,800 bph

Power Reserve

66 hours

Year

1966

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