DEWALT DW5746 3/4-Inch by 5-Inch by 10-Inch 4-Cutter Spline Shank Rotary Hammer Bit<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>ROCK CARBIDE tip maximizes carbide surface contact for longer bit life.</li><li>Open head design channels dust into flutes for quicker drilling</li><li>Longer helix four flute design expedites mill removal for quicker drilling.</li><li>Concave head design allows dust to enter flute chambers quickly increasing bit life</li><li>One year warranty， one year service contract， 30 day no-risk trial</li></ul></div><img src="http://ecx.images-amazon.com/images/I/31HEEycislL.jpg" noproxy>