Hammers and striking tools drive nails and join and separate parts. Axes, hatchets, and splitting wedges are used for chopping, splitting, notching wood, cutting trees, or slicing through brush. Ball peen hammers, also known as ball pein hammers, are used to drive cold chisels, set rivets, and bend and shape metal. Claw hammers have claw ends that are used to pull nails or separate boards. Dead blow hammers have heads filled with lead shot or sand to prevent the hammer from bouncing back toward the worker after impact. Rubber and wooden mallets have a large face to evenly distribute force over a workpiece and reduce the risk of damaging materials. Sledgehammers have heavy-duty heads to drive wedges and posts or perform heavy demolition work.