DEWALT Wood Auger Drill Bits have a threaded centre point to aid accurate drilling. The outer cutting spur provides clean holes with less splintering and the drill bits feature a special Lewis spiral flute which allows for fast removal of debris and rapid drilling. Ideal for rapid, precise drilling. Typically used for boring clean precise holes through beams, joists, doors, etc. Sizes 6-10mm have cylindrical shanks and sizes 12-32mm have hexagonal shanks. Ref: UTTK5742