Abstract: The present invention provides a device (1) for creasing, perforating and/or folding paper or other similar media to suit envelopes of various sizes. The device (1) includes a selectable creasing (15) or perforating head (20) which cooperates with an anvil (35), a Top Of Form sensor (46), a jam roller (59), associated pinch rollers (49, 63, 66) and a firmware for entering the paper size and type of paper for folding. After a predetermined paper length is fed into the paper path, the creasing (15) or perforating head (20) traverses a width of the paper to form a crease and after a predetermined length of paper passes the Top Of Form sensor (46), the jam/pinch rollers (59/49, 63, 66) are programmed to reverse in direction to cause the paper to buckle at the crease to form a fold. The types of folding operable by the device (1) are: letter, z, engineering, gate or half-fold.