a motorized drum has a drum shell having an inner periphery and a central axis , with a motor and a reducer disposed therewithin for delivering rotary power to the drum shell at a determined region thereof . a mounting face system has a mounting face arrangement that receives components to be attached to alter the length of the motorized drum . the mounting face arrangement is disposed at an end of the motorized drum distal from the region where the reducer delivers power to the drum shell . the mounting face arrangement limits the flexure of the attachable components such that the deflection curve is continuous to reduce stress concentration .