8218MIYOTA Watch Movement Cal.8218, Standard Automatic movement.Size: Heh: -YOUR ENGINE8218, 0.2 mm Japanese: Shaft Diameter: ф10 mm (ф 12 mm Internal) Shaft Length: 9.5 mm: Motor Diameter: ф89 mm: Motor Rotor Inertia: 3.260 kg*cm^2: Motor Length: 54.2 mm: Motor