Seiko Cal. 4525 - 840

The Seiko 4525-840 represents an important milestone in Seiko's 1977 lineup. Powered by the 4525 caliber with 31j jewels beating at 28,800 bph, it delivers a 66 hours power reserve. [seikata-wm-9b57550f3089]

Also known as: Helmet, Baby Tuna

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

36mm

Case Thickness

12.6mm

Lug Width

21mm

Crystal

Acrylic

Bezel

Inner Rotating

Water Resistance

150m

Dial Color

Silver

Jewels

31j

Frequency

28,800 bph

Power Reserve

66 hours

Year

1977

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