Seiko Cal. 5631 - 863

The Seiko 5631-863 represents an important milestone in Seiko's 1973 lineup. It features a Black dial protected by a Hardlex crystal and offers 40m of water resistance. [seikata-wm-bc7b14cebf2f]

Also known as: Navigator, Golden Tuna

Specifications

Movement

Hand-Winding

Case Material

Two-Tone

Case Width

36mm

Case Thickness

15.0mm

Lug Width

19mm

Crystal

Hardlex

Bezel

Coin-Edge

Water Resistance

40m

Dial Color

Black

Jewels

27j

Frequency

28,800 bph

Power Reserve

46 hours

Year

1973

Related Models

• Seiko 4433-430
• Seiko 4542-435
• Seiko 4470-170
• Seiko 6321-470
• Seiko 6173-724
• Seiko 3868-577
• Seiko 4548-542
• Seiko 6193-728
• Seiko 3897-334
• Seiko 3879-864
• Seiko 6155-309
• Seiko 7134-483