DeWALT 1 2" x 16" x 18" SDS Plus 2 Cutter Hammer Bit DW5440 Contractor Router Bits D1 4 spindle precision ground for D1 4 spindle precision ground for accuracy with class 7 tapered roller bearings 3 Flute Carbide Cutting Edge three flutes produce more cuts per revolution than a standard two flute bit Two stage flute design with variable helix pattern efficiently moves debris away from the contact zone for faster The tapered core design specifically addresses the common problem of flute breakage during deep hole drilling a critical advantage when working in reinforced concrete or thick masonry where bit failure can cost significant time and money