Most towers employ fills to facilitate heat transfer by maximizing water and air contact.
There are two types of fill:

Film fill: consists of thin, closely spaced plastic surfaces over which the water spreads, forming a thin film in contact with the air.

Splash fill: water falls over successive layers of horizontal splash bars, continuously breaking into smaller droplets, while also wetting the fill surface.
The PVC film sheet or splash bar should be specially designed for cooling tower.
Fill support shall be made of FRP or SS in form of grate.