This is very powerful "1833" size motor suitable for medium and larger 7mm/ft. scale also some larger 4mm/ft. scale models providing substantially more torque than similar sized Mashima motors. The motor is very quiet as shown by the noise figures documented by the manufacturer below. The drive shaft is 2mm in diameter. This motor will fit gearboxes designed for Canon EN22 motors as the mounting holes have the same pitch. The front bearing retainer is slightly wider than the Canon so the hole on the gearbox may need to be reamed out by a millimeter or so. We can supply an etched gearbox to use this motor with Ultrascale 40:1 or 20:1 gears.