Seiko Cal. 6660 - 427

The Seiko 6660-427 represents an important milestone in Seiko's 1981 lineup. Powered by the 6660 caliber with 25j jewels beating at 28,800 bph, it delivers a 57 hours power reserve. [seikata-wm-428779264cdf]

Also known as: Helmet, Baby Tuna

Specifications

Movement

Hand-Winding

Case Material

Hardlex-Coated Steel

Case Width

34mm

Case Thickness

14.5mm

Lug Width

21mm

Crystal

Acrylic

Bezel

Fixed

Water Resistance

170m

Dial Color

Blue Sunburst

Jewels

25j

Frequency

28,800 bph

Power Reserve

57 hours

Year

1981

Related Models

• Seiko 6218-485
• Seiko 7130-706
• Seiko 6172-693
• Seiko 4421-560
• Seiko 6387-188
• Seiko 5223-250
• Seiko 6118-700
• Seiko 7080-900
• Seiko 4545-351
• Seiko 6187-218
• Seiko 6238-178
• Seiko 5299-864