Seiko Cal. 6637 - 503

This Hand-Winding model from 1981 features a 37mm Gold-Plated case. It features a Silver dial protected by a Acrylic crystal and offers 140m of water resistance. [seikata-wm-448a16fe126e]

Also known as: Tuna, Rally

Specifications

Movement

Hand-Winding

Case Material

Gold-Plated

Case Width

37mm

Case Thickness

14.5mm

Lug Width

20mm

Crystal

Acrylic

Bezel

Inner Rotating

Water Resistance

140m

Dial Color

Silver

Jewels

25j

Frequency

36,000 bph

Power Reserve

67 hours

Year

1981

Related Models

• Seiko 5266-723
• Seiko 6657-813
• Seiko 5264-115
• Seiko 3891-422
• Seiko 7044-795
• Seiko 6652-358
• Seiko 6140-465
• Seiko 6627-252
• Seiko 5226-450
• Seiko 7018-990
• Seiko 6145-399
• Seiko 7097-455