Seiko Cal. 3868 - 640

The Seiko 3868-640 represents an important milestone in Seiko's 1979 lineup. Powered by the 3868 caliber with 36j jewels beating at 21,600 bph, it delivers a 49 hours power reserve. [seikata-wm-75bbc1735b58]

Also known as: Helmet, Baby Tuna

Specifications

Movement

Hand-Winding

Case Material

Titanium

Case Width

34mm

Case Thickness

11.4mm

Lug Width

19mm

Crystal

Acrylic

Bezel

Bidirectional

Water Resistance

150m

Dial Color

Green

Jewels

36j

Frequency

21,600 bph

Power Reserve

49 hours

Year

1979

Related Models

• Seiko 4435-686
• Seiko 6680-270
• Seiko 3846-896
• Seiko 6689-702
• Seiko 5236-160
• Seiko 6648-275
• Seiko 7012-452
• Seiko 4452-187
• Seiko 7188-805
• Seiko 6250-667
• Seiko 3841-364
• Seiko 6378-660