Angle grinder is a handheld power tool, which is used for grinding and polishing. It can be powered by an electric motor, petrol engine or compressed air. The motor drives a geared head at a right-angle on which is mounted an abrasive disc that can be renewed when worn. Angle grinders typically have an adjustable guard and a side-handle for two-handed operation. There are myriad different disks that are used for various materials and tasks, such as cut-off disks, abrasive grinding disks, sanding disks, wire-brush wheels and polishing pads. The angle grinder has large bearings to counter side forces generated during cutting, unlike a power drill, where the force is axial. These are widely used in metalworking and construction, as well as in emergency rescues.