-The 402 mandrels is used primarily with cut-off wheels but is used with the following Dremel accessories: 409, 411, 412, 413, 420, 423, 425, 426, 456, 511, 512, 540 and 541-Used primarily with Dremel polishing bits and accessories-For use in all Dremel rotary tools1/8 In. shank(User Tips)Insert the small screw through the hole in the cut-off wheel then tighten the screw into the mandrel’s threaded head.