The sheet-fed press prints on individual sheets of paper, as opposed to continuous rolls of paper used on web presses. Sheet-fed presses come in different sizes. Quick printers often use the small presses which print on letter size pages. The larger commercial sheet-fed presses handle much larger sheets of paper. Sheet-fed presses can also print on cardstock, plastics, metal, and other substrates. A sheet-fed press may consist of multiple print units that each print a different color of ink.