Seiko Cal. 4487 - 991

The Seiko 4487-991 represents an important milestone in Seiko's 1991 lineup. The Inner Rotating bezel and 42mm case give it a distinctive presence on the wrist. [seikata-wm-bad2fb899988]

Also known as: Bullhead, Navigator

Specifications

Movement

Spring Drive

Case Material

Stainless Steel

Case Width

42mm

Case Thickness

9.4mm

Lug Width

21mm

Crystal

Sapphire

Bezel

Inner Rotating

Water Resistance

60m

Dial Color

Blue Sunburst

Jewels

24j

Frequency

28,800 bph

Power Reserve

39 hours

Year

1991

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