Nickel plated with a tungsten carbide tip. All drill bits listed over 13mm are reduced down to fit a standard 13mm chuck. The solid design is fully hardened, it is perfect for use in brick, masonry and tiles. Percussion masonry drill bit. It is ideal both for professional use (carpenters, plumbers, electricians, etc.) and for DIY enthusiasts. High Performance Drill Bit with Straight Shank design.