- Seiko 66B
- manual-wind
- sweep second
- 10.5”’
- Dm= 23.60mm
- H= 3.85mm
- 17 jewels
- f = 18000 A/h
- power reserve 45h
- family/generations:
- Seiko 66A: manual wind
- Seiko 6601A: automatic
- modified hands gear:
- Seiko 66B, 436, 4361: manual wind
- Seiko 6601B: automatic
- Seiko 6602B: manual wind, date
- Seiko 6606B: automatic, day, date
- Seiko 6619B: automatic, day, date quickset