The "Advance" cooling towers operate on the counter flow principle which gives the best performances. The air flow through the tower infill is opposed to the water flow. The cold air meets the cooled water at the bottom of the infill providing maximum evaporation and heat transfer in the infill. The PVC infill is corrugated with clear channels between flutes to prevent any blockage and giving a large surface area per unit volume. Water flows through the infill in a thin film exposing the maximum area to the cooling air flow. The flutes of the infill are at an angle and each layer of infill section is reversed, turning the film or water and air over for maximum cooling.