Seiko Cal. 4428 - 636

The 4428-636 is a sought-after Kinetic piece from Seiko's golden era. Powered by the 4428 caliber with 21j jewels beating at 36,000 bph, it delivers a 59 hours power reserve. [seikata-wm-0d68b1083144]

Also known as: Bullhead, Bellmatic

Specifications

Movement

Kinetic

Case Material

Hardlex-Coated Steel

Case Width

35mm

Case Thickness

14.0mm

Lug Width

20mm

Crystal

Hardlex

Bezel

Fixed

Water Resistance

180m

Dial Color

White

Jewels

21j

Frequency

36,000 bph

Power Reserve

59 hours

Year

1983

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