Seiko Cal. 3820 - 640

The Seiko 3820-640 represents an important milestone in Seiko's 1975 lineup. Powered by the 3820 caliber with 30j jewels beating at 21,600 bph, it delivers a 60 hours power reserve. [seikata-wm-2d8970f767d0]

Also known as: World Timer, Emperor

Specifications

Movement

Quartz

Case Material

Stainless Steel

Case Width

45mm

Case Thickness

13.4mm

Lug Width

22mm

Crystal

Mineral

Bezel

Rotating

Water Resistance

130m

Dial Color

Cream

Jewels

30j

Frequency

21,600 bph

Power Reserve

60 hours

Year

1975

Related Models

• Seiko 7198-139
• Seiko 5245-561
• Seiko 5628-428
• Seiko 4541-397
• Seiko 3861-470
• Seiko 5660-963
• Seiko 6341-583
• Seiko 3846-743
• Seiko 6285-722
• Seiko 6214-704
• Seiko 7195-494
• Seiko 5212-855