The Martin Yale Master® 1340PB Heavy Duty 2-Hole & 3-Hole Punch offers versatility for hole punching, with the built-in ability to punch either two or three holes by just adjusting the punching heads, as well as the add-on ability to punch up to seven holes by just adding additional punch heads (not included). Over-sized 13/32" holes make for the easiest page turning available, making the holes less likely to tear. It also adds the ability to use binding methods other than traditional binders, such as prong fasteners. The ability to punch as many as 40 sheets* at a time means you can get more done in one pass than many other punchers out there. The adjustable paper guide features ruled measurements for precise paper centering, and the adjustable margin depth lets you set the holes as deep into your sheet as 1/4". When you buy the Martin Yale Master® 1340PB Heavy Duty 2-hole & 3-hole punch online, you are getting a heavy duty paper punch.