Seiko Cal. 3872 - 840

Released in 1966, the Cal. 3872 with design code 840 was part of Seiko's domestic market collection. Powered by the 3872 caliber with 21j jewels beating at 36,000 bph, it delivers a 72 hours power reserve. [seikata-wm-a4aed3a9ec98]

Also known as: Sea Horse, Baby Tuna

Specifications

Movement

Hand-Winding

Case Material

Two-Tone

Case Width

39mm

Case Thickness

15.2mm

Lug Width

18mm

Crystal

Sapphire

Bezel

Fixed

Water Resistance

40m

Dial Color

Navy

Jewels

21j

Frequency

36,000 bph

Power Reserve

72 hours

Year

1966

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