Kreg LH-DKDB 3/8-Inch Left-Hand Step Drill Bit for DK3100 Pocket Hole Machine
The one-piece design elminates clogging and provides a much smoother and faster drilling stroke than other pocket hole drill bits.  The step drill bit drills the pocket hole and the pilot hole in one process.  Made with Cobalt steel to increase drill bit life.  For use specifically in Kreg's DK3100 Multi-Spindle Pocket Hole Machine.  Not for use with any other pocket hole machine or manual jig.