Seiko Cal. 4420 - 520

The 4420-520 is a sought-after Spring Drive piece from Seiko's golden era. Powered by the 4420 caliber with 23j jewels beating at 36,000 bph, it delivers a 45 hours power reserve. [seikata-wm-c48df5d3d576]

Also known as: Baby Tuna, Emperor

Specifications

Movement

Spring Drive

Case Material

Stainless Steel

Case Width

41mm

Case Thickness

15.7mm

Lug Width

18mm

Crystal

Sapphire

Bezel

Inner Rotating

Water Resistance

30m

Dial Color

Navy

Jewels

23j

Frequency

36,000 bph

Power Reserve

45 hours

Year

1975

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