3/8" Red Plastic Binding Combs - 100pk MyBinding PC380RD Red Hole Pattern: 19 Hole Approximate Capacity: 55 Sheets Length: 11" (19 Rings) Shape: Round <span class="a-text-bold">Construction.</span> How well-built is the machine? <span class="a-text-bold">Control.</span> If you want a machine that can bind documents of different sizes, look for a machine with disengageable dies. If controlling the placement of the holes is important because youll be using combs of different thicknesses, a depth of punch margin control is a must-have. <span class="a-text-bold">Quantity.</span>If youre an individual or a small business owner who will only be binding once in a while, a personal-sized machine is ideal. However, for higher-volume outfits such as copy centers, a professional-grade machine is better.