A special variation is the ‘pony press’, which prints on both sides of the paper with only four printing units, and so requires only four cylinders. The paper web width is just less than half the width of the cylinders. The paper travels through the press at one side of the paper path, and then is led from the last printing unit back to the first, passing round ‘turner bars’ which move the web to the other side of the paper path and turn it over, so it can then pass through the press a second time, next to itself but upside down, to be printed on the second side.