The CD-C800 is a 4 speed Cardi high torque gearbox that is very good for drilling deep or large holes up to 30” diameter.
It will accept most 400 HZ motors with a 3½” X 3½” flange mount and ⅝” spline coupler (AN2001). It has approximately a 3.7:1 ratio between low & high gear.
It is super strong, light weight and is well liked by drillers.