The Zak Tool #64 Shove Knife is a forcible entry tool used by police and firefighters. It quickly opens most key-in-knob locks for residential and commercial interior doors. The Shove Knife will work for doors that open inward or outward. For inward opening doors, insert the Shove Knife as far as you can and pull toward you to open the latch. For outward opening doors, place the Shove Knife above or below the latch, then jiggle and pull back to release the latch. 6" long.