Seiko Cal. 4550 - 552

The Seiko 4550-552 represents an important milestone in Seiko's 1965 lineup. The Rotating bezel and 40mm case give it a distinctive presence on the wrist. [seikata-wm-2fc0a3203b74]

Also known as: Helmet, Bellmatic

Specifications

Movement

Automatic

Case Material

Titanium

Case Width

40mm

Case Thickness

13.3mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Rotating

Water Resistance

140m

Dial Color

Blue Sunburst

Jewels

32j

Frequency

28,800 bph

Power Reserve

45 hours

Year

1965

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