Keep the air around you cool inside and outside your home. With the Hessaire Portable Evaporative Air Cooler, you can stay cool inside your home, out on your patio, or at your campsite. Just plug it in and you're ready to chill. Evaporative coolers are more commonly known as "swamp coolers." These air cooling systems cool warm, stale air with natural evaporation. As water inside the swamp cooler evaporates into the air circulating through the cooling system, the air lowers in temperature. Evaporative wet air coolers are ideal