A rotary hammer, also called rotary hammer drill is a power tool that can perform heavy-duty tasks such as drilling and chiseling hard materials. It is similar to a hammer drill in that it also pounds the drill bit in and out while it is spinning. However, rotary hammers use a piston mechanism instead of a special clutch. Rotary hammers can be used for “doweling” (repetitive drilling of large rebar anchor holes), and drilling through-holes in concrete and masonry walls. The hammering action helps break up the masonry so that it can be removed by the drill bit’s flutes. Apart from their main function of drilling concrete, the rotary action can be switched off and use is made of just the percussive force. Chisel and point accessories are used for small chipping jobs.