Seiko Cal. 4540 - 831

This Automatic model from 1965 features a 41mm PVD Black case. With its 18mm lug width and 15.2mm profile, it sits comfortably on most wrists. [seikata-wm-98e0b2df4fad]

Also known as: Tuna, Crown

Specifications

Movement

Automatic

Case Material

PVD Black

Case Width

41mm

Case Thickness

15.2mm

Lug Width

18mm

Crystal

Sapphire

Bezel

Inner Rotating

Water Resistance

140m

Dial Color

Blue Sunburst

Jewels

27j

Frequency

28,800 bph

Power Reserve

53 hours

Year

1965

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