Seiko Cal. 5240 - 720

This Spring Drive model from 1981 features a 37mm Titanium case. Powered by the 5240 caliber with 31j jewels beating at 28,800 bph, it delivers a 37 hours power reserve. [seikata-wm-31c31ddb959a]

Also known as: Baby Tuna

Specifications

Movement

Spring Drive

Case Material

Titanium

Case Width

37mm

Case Thickness

14.6mm

Lug Width

19mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

100m

Dial Color

Black

Jewels

31j

Frequency

28,800 bph

Power Reserve

37 hours

Year

1981

Related Models

• Seiko 4538-565
• Seiko 7188-161
• Seiko 6260-604
• Seiko 5283-975
• Seiko 5216-699
• Seiko 4522-940
• Seiko 3846-907
• Seiko 6678-447
• Seiko 5244-238
• Seiko 7177-503
• Seiko 6290-721
• Seiko 7137-485