Electric Three-hole Desktop Punch drills through 10 sheets of 20 lb. paper at a time consistently without jamming. Punch creates 9/32" holes for easy page turning. Button on top makes it easy to activate. Simply push and punch effortlessly. Adjustable paper guide is built into the base. Large chip holder in base gives you plenty of disposal space. Punch includes AC adapter or use with six AA batteries (sold separately). Battery use provides enough power to operate it for a year of average use.