The Smart-Bit Pre-drilling and Countersinking Tool is designed for decking and general woodworking. The tool features a pre-set countersink, a free spinning stop collar to protect the work surface, and replaceable Powerbolic fluted drill bits that cut through decking more than twice as fast as standard wood bits. Unlike conventional flush mounted countersinks, the Smart-Bit has an anti-clog debris cavity that gathers the waste material keeping it clear of the countersink. The waste simply falls to the deck surface after each hole is completed. The Smart-Bit tool comes with two extra replacement bits and a 3/32" hex wrench for use with the set screw that holds the drill bits in place. Replacement bits are also sold separately.