Champion CM79-7/8 Proline 7/8-Inch Rotary Rebar Cutter 1/2-Inch Shank Rotary Rebar Cutters are carbide tipped and have a 1/2-Inch shank. Easy drilling through embedded rebar and surrounding concrete. Use in any 1/2-Inch capacity or larger drill motor with a three jaw chuck and no load speed of 440 rpm. Application: Drill first with a hammer drill bit(1) until reaching rebar. Replace bit with CM79 drill then penetrate rebar(2). After completion of rebar drilling, complete drilling with hammer bit(3).