Seiko Cal. 6643 - 403

The Seiko 6643-403 represents an important milestone in Seiko's 1971 lineup. With its 18mm lug width and 9.6mm profile, it sits comfortably on most wrists. [seikata-wm-fe3fda6d9fd8]

Also known as: Bullhead

Specifications

Movement

Solar

Case Material

Hardlex-Coated Steel

Case Width

39mm

Case Thickness

9.6mm

Lug Width

18mm

Crystal

Sapphire

Bezel

Bidirectional

Water Resistance

170m

Dial Color

Burgundy

Jewels

25j

Frequency

36,000 bph

Power Reserve

41 hours

Year

1971

Related Models

• Seiko 6264-859
• Seiko 0725-641
• Seiko 4433-243
• Seiko 6320-903
• Seiko 4576-744
• Seiko 4491-594
• Seiko 7075-314
• Seiko 7051-777
• Seiko 6238-884
• Seiko 5650-234
• Seiko 4476-418
• Seiko 7038-524