The 3M mini mandrel is designed to work with your die grinder or rotary tool. This accessory grips a 1 in W strip of Scotch-Brite non-woven material allowing you to access tight internal diameters, typically for surface conditioning or polishing tasks. The 3M mini mandrel is an accessory that attaches to your die grinder or drill. It holds a 1 in W strip of Scotch-Brite non-woven material. Secure its shaft into the collet assembly of your drill chuck or rotary power tool-to clean, polish or deburr the inside diameter of the workpiece. The 2-7/8 in L mini mandrel is useful in metal fabrication, woodworking and millwork, in the manufacture of medical instruments, turbine engine manufacture, plumbing and other industries where finishing internal diameters is necessary.