MB usually offers arrangements providing for counter and cross flow operation, typical of theEuropean school. Supporting structures are made of reinforced concrete, either in place orprefabricated, or in special treated stainless steel material or galvanized steel. The filling system ismade from plastic material, either PVC or polypropylene, water to be cooled-to-air contact system isfilm-type, splash-type or a combination of the two. Fan units operate under forced draft conditions,with blower fans installed at the bottom of the tower, or under induced draft conditions with suctionfans installed at the top of the tower.