Seiko Cal. 4431 - 540

The Seiko 4431-540 represents an important milestone in Seiko's 1965 lineup. With its 18mm lug width and 14.9mm profile, it sits comfortably on most wrists. [seikata-wm-1e7658ea90e7]

Also known as: Sportsmatic, Emperor

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

45mm

Case Thickness

14.9mm

Lug Width

18mm

Crystal

Hardlex

Bezel

Rotating

Water Resistance

190m

Dial Color

Green

Jewels

17j

Frequency

21,600 bph

Power Reserve

58 hours

Year

1965

Related Models

• Seiko 4429-854
• Seiko 4539-403
• Seiko 6162-214
• Seiko 6133-518
• Seiko 5625-232
• Seiko 6663-381
• Seiko 3840-791
• Seiko 6634-831
• Seiko 6640-541
• Seiko 0723-806
• Seiko 6170-885
• Seiko 5276-425