Seiko Cal. 4540 - 646

The Seiko 4540-646 represents an important milestone in Seiko's 1974 lineup. The Bidirectional bezel and 43mm case give it a distinctive presence on the wrist. [seikata-wm-dbdef54aac66]

Also known as: Helmet, Baby Tuna

Specifications

Movement

Quartz

Case Material

Gold-Plated

Case Width

43mm

Case Thickness

10.1mm

Lug Width

22mm

Crystal

Hardlex

Bezel

Bidirectional

Water Resistance

150m

Dial Color

White

Jewels

20j

Frequency

36,000 bph

Power Reserve

42 hours

Year

1974

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