The super absorbent fiber weave technology of the mesh towel regulates the water inside and ensures water retention . so it's treating it kind of like an air-conditioner . and within seconds you get cooler.
Like sweat on you skin . when water evaporates it cools. Any ole cotton or microfiber towel would work . but not as well design to maximize evaporative cooling or comfort.
If you are sweating a lot . rinse the 'salty water' out from time to time. Salt reduces evaporation/cooling rate