The Irwin Cordless Multi-Purpose Drill Bits have been designed for cordless, low speed multi-purpose drilling. They offer around 10% extra battery life per charge. They have a four-facet ground carbide tip for lower drilling pressure and better centring and allow for combined drilling into wood and brickwork: the Cordless Drillbit is excellent for such drilling jobs - where you drill through wood into brickwork. Only one drillbit is needed to do the job and will drill a wide selection of different materials like:BrickworkCeramic TilesBreeze BlockWoodDry WallGypsum BoardLimestoneSlateMarbleEternitePlastics/Reinforced plastics.Length: 80mm Diameter: 4.0mm Flute Length: 41mm