The machine constantly feeds cartons into the bundler very rapidly. When they reach the end of the belt three cartons are pressed on either side by rubber plates, and three more cartons enter below them. These six cartons are then moved upwards by a metal lift and on the way a piece of plastic is placed on top of them. When they are lifted to the top of the bundler, a metal plate slides under the bundle of cartons from behind and pushes the plastic wrap under them. Then a metal plunger pushes the bundle forward which forces the wrap from the other end to move under the bundle. The bundle is then pushed forwards by other bundle and the excess wrap is cut off the metal blades. Finally the bundle is pulled by heated belts on either side of the bundle which heat the plastic just enough in order to stick together without melting