Bosch 2607010522 CYL-9 Multi Construction Drill Bit Set (4 Piece) The CYL-9 MultiConstruction Drill Bit delivers stable drilling in all kinds of materials. Its centring tip provides a steady drilling start and good guidance universally. Additionally, the bit\'s 4-flute dura design with a reinforced core section delivers better wear resistance and stability when drilling soft concrete. The bit is intended for practically all materials in interior fitting work, e.g. soft concrete, masonry, brick, cement asbestos, light building materials, multilayer materials, ceramics and tiles, wood, plastic, sheet metals and aluminium. It is compatible with cylindrical shank systems for all corded or cordless drills, enabling perfect results when drilling with or without impact.  Features: Centring tip provides a steady drilling start and good guidance universally Diameter-optimised AWB brazing and hardening technology increases robustness and reduces vibration during use 4-flute dura design with a reinforced core section delivers better wear resistance and stability when drilling in soft concrete