Manufacturer Seiko Caliber Number 6R20, 6R20A Movement Type Automatic, self-winding mechanical In-House? Yes Diameter 27.40mm (outside), 27mm (casing) Height 6.15mm...
6R15
Manufacturer Seiko Caliber Number 6R35, 6R35A Movement Type Automatic Diameter 27.40mm (needs confirmed) Casing Diameter 27mm (needs confirmed) Height 5.25mm...
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...