Manufacturer Seiko Caliber Number 6R20, 6R20A Movement Type Automatic, self-winding mechanical In-House? Yes Diameter 27.40mm (outside), 27mm (casing) Height 6.15mm...
Seiko 6R27
Manufacturer Seiko Caliber Number 6R15 (A/B/C/D) Movement Type Automatic Diameter 27.40mm (outside), 27mm (casing) Height 5.25mm Jewels 23/24 Vibrations Per...
Manufacturer Seiko Caliber Number 6R27 Base Caliber 6R15 (6R family) Movement Type Automatic Jewels 29 Vibrations Per Hour 28,800 bph...