Seiko Cal. 6631 - 490

This Spring Drive model from 1971 features a 46mm Hardlex-Coated Steel case. Powered by the 6631 caliber with 23j jewels beating at 21,600 bph, it delivers a 48 hours power reserve. [seikata-wm-48d2c334e19d]

Also known as: Turtle, Baby Tuna

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

46mm

Case Thickness

9.4mm

Lug Width

20mm

Crystal

Mineral

Bezel

Fixed

Water Resistance

30m

Dial Color

Navy

Jewels

23j

Frequency

21,600 bph

Power Reserve

48 hours

Year

1971

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