Special concrete & masonry drill bits are used for drilling in brickwork and concrete. For the proper installation of components, drill bits from a certified manufacturer should be used. The drill-hole tolerances may be exceeded if you use drill bits which have not been monitored during production. Bits with too much true-running deviation or too high tolerances in the tungsten carbide cutting edge can result in drill holes with not enough grip for an anchor. In the extreme, the installed elements will loosen and cause severe damage. In the case of concrete drill bits, it is even recommended that you only use products which have been manufactured in accordance with the guidelines of the Prüfgemeinschaft Mauerbohrer (PGM), an independent institute. You can recognise this by the quality mark or the symbol stamped on the drill bit.