These high-performance Faithfull Tungsten Carbide Tipped Drill Bits fit into SDS Plus chucks which provide a particularly secure non-slip grip that transmits maximum power for rotary percussion drilling, mainly into concrete. The SDS Plus bits ensure maximum power transmission due to their unique fluted shaft. This effectively removes situations where a perfectly serviceable cutting edge is rendered useless by a worn shank. The SDS Plus system also enables faster changing of drills using a quick release keyless chuck. For use in bricks, blocks, concrete containing aggregates, marble and hard stone, and other hard masonry materials.4 Piece Faithfull SDS Plus Drill Bit Set supplied in a handy plastic case. Contains the following sizes: 5.5mm, 6mm, 7mm & 8mm. All have a working length of 100mm.Additional Information:• Pack Qty.: 4