The shank of the mandrel must match the size of the power tool collet or drill chuck, and the pilot diameter must be compatible with the size of the cartridge roll.
3M 45116, Cartridge RoII Mandrel, 1/4 in x 1-1/2 in x 1/4 in, 7010328350
$4.16
Factory Stock, 7-10 Day Leadtime
3M Cartridge Roll Mandrel is a tool attachment that holds an abrasive cartridge roll (sold separately). Together, the mandrel and cartridge roll enable the user to grind or finish hard-to-reach areas of a workpiece, such as angles and curves. The mandrel attaches to a rotary tool such as a die grinder or drill, and comes in different sizes to fit a variety of cartridge roll sizes.

3M 22408, Roloc Disc 361F, P100 YF-weight, TR, 1-1/2 in, Die R150S, 7000045101
3M 05520, Sanding Block, Rubber, 2-3/4 in x 8 in, 7000028366
3M 05783, Hookit Pad D/F, 8 in x 5 bolt hole, 7000119884 
