In web offset lithography, a means of perfecting in which a paper web of half the diameter of the plate and plate cylinder is run through the press. The "half web" is aligned with one edge of the plate and run through the press. It is dried, flipped over, and aligned with the other edge of the plate, where the second side is laid down. In some configurations—a process referred to as double-ending— two half webs are run through simultaneously. See Web Offset Lithography: Press Configurations.