Seiko Cal. 6636 - 421

The Seiko 6636-421 represents an important milestone in Seiko's 1973 lineup. Powered by the 6636 caliber with 36j jewels beating at 36,000 bph, it delivers a 44 hours power reserve. [seikata-wm-17ff01f0d20f]

Also known as: Monster, Sumo

Specifications

Movement

Quartz

Case Material

Hardlex-Coated Steel

Case Width

44mm

Case Thickness

9.0mm

Lug Width

19mm

Crystal

Acrylic

Bezel

Fixed

Water Resistance

110m

Dial Color

White

Jewels

36j

Frequency

36,000 bph

Power Reserve

44 hours

Year

1973

Related Models

• Seiko 3883-503
• Seiko 7161-794
• Seiko 5224-944
• Seiko 6272-193
• Seiko 6681-920
• Seiko 6196-877
• Seiko 0756-229
• Seiko 7176-602
• Seiko 4596-246
• Seiko 6132-852
• Seiko 6250-849
• Seiko 6257-394