Seiko Cal. 5645 - 666

The 5645-666 is a sought-after Spring Drive piece from Seiko's golden era. Powered by the 5645 caliber with 36j jewels beating at 21,600 bph, it delivers a 57 hours power reserve. [seikata-wm-b633c1ab2df6]

Also known as: Helmet

Specifications

Movement

Spring Drive

Case Material

Gold-Plated

Case Width

37mm

Case Thickness

11.5mm

Lug Width

19mm

Crystal

Mineral

Bezel

Inner Rotating

Water Resistance

190m

Dial Color

Navy

Jewels

36j

Frequency

21,600 bph

Power Reserve

57 hours

Year

1968

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