MasterCool 36-1/4 in. H X 35-1/2 in. W Brown Cellulose Evaporative Cooler Pad

Evaporative cooling pad uses the simple principle of cooling by evaporation i.e. passing hot fresh air through the wet and cool surface to bring temperatures down. Sensible heat is thereby changed to latent heat and fresh air leaving the pads is humidified and cold.