Drill Doctor DA02105PF Left Hand Chuck (Fits models DD500X, DD750X). A left-handed drill bit actually backs out the original broken bolt without damaging the existing threads.
Holds left-handed (reverse twist) 3/32” to 1/2” drill bits. Left-handed drill bits are used to remove broken bolts without creating an oversized hole, which would result in having to use a larger bolt to replace the one removed. 3/32" to 1/2" Drill Dr. Left-Handed Chuck.