Seiko Cal. 6640 - 545

The 6640-545 is a sought-after Automatic piece from Seiko's golden era. Powered by the 6640 caliber with 24j jewels beating at 21,600 bph, it delivers a 50 hours power reserve. [seikata-wm-a93cc8f3f745]

Also known as: Monster, Sumo

Specifications

Movement

Automatic

Case Material

Titanium

Case Width

38mm

Case Thickness

8.5mm

Lug Width

18mm

Crystal

Sapphire

Bezel

Fixed

Water Resistance

160m

Dial Color

Silver

Jewels

24j

Frequency

21,600 bph

Power Reserve

50 hours

Year

1967

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