Seiko Cal. 4431 - 633

The Seiko 4431-633 represents an important milestone in Seiko's 1976 lineup. Powered by the 4431 caliber with 28j jewels beating at 36,000 bph, it delivers a 60 hours power reserve. [seikata-wm-b98873061266]

Also known as: UFO, Arnie

Specifications

Movement

Quartz

Case Material

PVD Black

Case Width

46mm

Case Thickness

10.5mm

Lug Width

22mm

Crystal

Sapphire

Bezel

Bidirectional

Water Resistance

180m

Dial Color

Blue Sunburst

Jewels

28j

Frequency

36,000 bph

Power Reserve

60 hours

Year

1976

Related Models

• Seiko 6283-313
• Seiko 3860-815
• Seiko 7186-810
• Seiko 7152-519
• Seiko 4497-848
• Seiko 3856-305
• Seiko 6233-195
• Seiko 3843-697
• Seiko 6243-788
• Seiko 6377-261
• Seiko 7195-490
• Seiko 6261-643