Plastic Pall Ring packing is a high hole diameter equal to the packing ring, each window there are five tongue leaves, each leaf tongue ring in turn point to heart, upper and lower levels of the location of the opposite window at different times and in general Central area of wall openings about the total area of about 30%. With porosity, and pressure drop and low height of mass transfer unit, the pan-point high, vapor-liquid contact with the full, the proportion of small, high mass transfer efficiency. This structure improves the vapor-liquid distribution, make full use of the inner surface of the ring, so that the tower fill the gas and liquid form from the free passage.