Seiko Cal. 6638 - 725

The Seiko 6638-725 represents an important milestone in Seiko's 1980 lineup. It features a Burgundy dial protected by a Mineral crystal and offers 90m of water resistance. [seikata-wm-debe2c3bf57d]

Also known as: Tuna

Specifications

Movement

Spring Drive

Case Material

Gold-Plated

Case Width

39mm

Case Thickness

11.3mm

Lug Width

22mm

Crystal

Mineral

Bezel

Bidirectional

Water Resistance

90m

Dial Color

Burgundy

Jewels

25j

Frequency

28,800 bph

Power Reserve

70 hours

Year

1980

Related Models

• Seiko 3820-442
• Seiko 6627-693
• Seiko 4587-214
• Seiko 5639-688
• Seiko 4550-723
• Seiko 3891-474
• Seiko 5256-713
• Seiko 3880-576
• Seiko 5267-782
• Seiko 6266-185
• Seiko 5266-498
• Seiko 5262-878