Eliminates the need to switch between different bit types, drilling into a multiplicity of materials. Can be used with rotary or percussion drills. Without percussion can be used on vitrified brick and wood; with percussion can be used on block, stone, plaster and most grades of concrete. Suitable for use with concrete, tile, brick, slate, limestone, wood, sandwich materials, aluminium, plastics and metals. Ideal for doors, shelves, window frames and more. Tungsten carbide tips for fast and efficient drilling. Steel Straight Shank 4mm-10mm Dia. Drill Bits Suitable for Concrete, Tile, Brick, Slate, Limestone, Wood, Sandwich Materials, Aluminium, Plastics & Metals Tungsten Carbide Tip For Use with 3-Jaw Chuck Machines on Rotary Action Steel Straight Shank 4mm-10mm Dia. Drill Bits Suitable for Concrete, Tile, Brick, Slate, Limestone, Wood, Sandwich Materials, Aluminium, Plastics & Metals Tungsten Carbide Tip For Use with 3-Jaw Chuck Machines on Rotary Action