The Confirmat Screw Step Drills from Snappy are designed so you can easily replace the brad point drill (sold separately) if it is damaged. Shanks are 1/4" hex so they can be changed for the PoziDrive driver bits in a snap. Use #2 PoziDrive with 5x40 Confirmat Screws and #3 with 7x50 Confirmat Screws.