8 piece stub auger bit set ideal for drilling between joists made from high quality carbon steel with screw thread and single spur they must only be used with torque control drills whats included1 x 8mm stub auger bit1 x 10mm stub auger bit1 x 13mm stub auger bit1 x 16mm stub auger bit1 x 19mm stub auger bit1 x 20mm stub auger bit1 x 25mm stub auger bit1 x 32mm stub auger bit1 x fabric tool case specifications shank diameter14 inch hex