Seiko Cal. 5640 - 689

This Spring Drive model from 1966 features a 35mm Titanium case. It features a Navy dial protected by a Mineral crystal and offers 150m of water resistance. [seikata-wm-ee31cd4b7273]

Also known as: Monster, Baby Tuna

Specifications

Movement

Spring Drive

Case Material

Titanium

Case Width

35mm

Case Thickness

15.4mm

Lug Width

19mm

Crystal

Mineral

Bezel

Coin-Edge

Water Resistance

150m

Dial Color

Navy

Jewels

22j

Frequency

36,000 bph

Power Reserve

48 hours

Year

1966

Related Models

• Seiko 7191-572
• Seiko 4410-967
• Seiko 6362-500
• Seiko 3841-929
• Seiko 6666-913
• Seiko 4579-375
• Seiko 0781-369
• Seiko 7089-525
• Seiko 6689-748
• Seiko 6298-147
• Seiko 4462-658
• Seiko 0771-747