TPS-Lock Shank System General Purpose Taper Point Replacement Drill Bits - Recommended for most jobs, whether in a drill press or in hand held equipment. Cuts very well in both hard and soft woods. To cut wood and plastics in one operation for the thread and shank of wood screws. Taper Point Drills are made of High Speed Steel to hold their sharp cutting edges longer. How to engage the TPS-Lock grip: Align the flat provided on the shank of the new replacement drill with the set screw hole. Use a small hammer to tap the shank onto the replacement drill. Replace and tighten the set screw. How to release the TPS-Lock grip: Loosen and remove the single hex socket set screw. Tap on the shank to drive it off the drill.