Blackdecker percussion hammer drills blackdecker kr504 gb this single speed percussion hammer drill from blackdecker is suitable for most home diy drilling projects the hammer action can drill into masonry up to 10mm but the drill can be used on a variety of materials including wood metal and plastic the kr204 gb is equipped with a high quality keyed chuck and lock on button for greater comfort blackdecker kr504 diy percussion hammer drill 500w 240v