Abstract: A drive collar is non-rotatably mounted for sliding movement on an arbor between working and release positions. In working position, the drive collar is disposed adjacent the base of a hole saw which is threadably mounted on an end of the arbor, and the collar and the hole saw are coupled for positively transmitting drive torque from the arbor to the saw. In release position, the drive collar is retracted from the saw and rendered inoperative for quick and easy assembly and disassembly of the saw and arbor.

Abstract: An arbor is provided for use with different size power tool chuck jaws and has a main body section of enlarged cross section relative to a shank of the arbor. The shank and main body section have a plurality of grooves therein with each groove longitudinally extending the length of the shank and into the adjoining main body section to define a continuous chuck jaw engaging surface which in the main body section of the arbor is of enlarged circumferential dimension relative to that of the shank drive surface for engaging different size chuck jaws in non-slipping positive driving relation.