Seiko Cal. 5640 - 631

Released in 1973, the Cal. 5640 with design code 631 was part of Seiko's domestic market collection. It features a White dial protected by a Mineral crystal and offers 200m of water resistance. [seikata-wm-5aca17bf79f9]

Also known as: Shogun

Specifications

Movement

Quartz

Case Material

Titanium

Case Width

40mm

Case Thickness

11.9mm

Lug Width

19mm

Crystal

Mineral

Bezel

Inner Rotating

Water Resistance

200m

Dial Color

White

Jewels

35j

Frequency

28,800 bph

Power Reserve

48 hours

Year

1973

Related Models

• Seiko 3894-890
• Seiko 6613-591
• Seiko 3819-394
• Seiko 5654-337
• Seiko 4489-436
• Seiko 6118-655
• Seiko 6162-646
• Seiko 6157-213
• Seiko 6375-869
• Seiko 3817-108
• Seiko 7037-544
• Seiko 3862-989