The Allwin super duty desktop 3-hole punch is capable of punching 150 sheets of 16# bond paper at a time. The elevated punch handle reduces punching effort.  Hole diameters are 7mm and slightly more than ¼-inch. This heavy duty punch comes equipped with adjustable side guide. The replaceable punch posts are designed with heart shaped blade to avoid breakage.  The base is made of thick ABS plastic for long life without extra weight.