Seiko Cal. 5661 - 420

The 5661-420 is a sought-after Kinetic piece from Seiko's golden era. Powered by the 5661 caliber with 27j jewels beating at 28,800 bph, it delivers a 70 hours power reserve. [seikata-wm-498f558b2e28]

Also known as: Monster, Helmet

Specifications

Movement

Kinetic

Case Material

Two-Tone

Case Width

45mm

Case Thickness

11.6mm

Lug Width

20mm

Crystal

Hardlex

Bezel

Rotating

Water Resistance

40m

Dial Color

White

Jewels

27j

Frequency

28,800 bph

Power Reserve

70 hours

Year

1983

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