The DEWALT DW1801 3/8-Inch Mandrel features double set screws with a recessed combination head for quick and easy centering bit changes. These mandrels also utilize hardened steel construction and have been tested through 15,000 cycles to deliver jobsite durability. DEWALT® offers a full range of standard and quick change mandrels for versatility in a wide range of hole saw applications. The improved pilot bit design gives longer life in all materials. Specifications: shank size 3/8. Chuck size 3/8. Hole saw size 9/16 to 1-3/16.