Seiko Cal. 3816 - 644

Released in 1968, the Cal. 3816 with design code 644 was part of Seiko's domestic market collection. Powered by the 3816 caliber with 32j jewels beating at 36,000 bph, it delivers a 50 hours power reserve. [seikata-wm-360feed7fff6]

Also known as: Sportsmatic

Specifications

Movement

Spring Drive

Case Material

Gold-Plated

Case Width

45mm

Case Thickness

12.7mm

Lug Width

22mm

Crystal

Sapphire

Bezel

Fixed

Water Resistance

100m

Dial Color

Champagne

Jewels

32j

Frequency

36,000 bph

Power Reserve

50 hours

Year

1968

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