???? Large 15L Water Tank with Dual Fill Design. Extra-large 15L water capacity. ✔ Evaporative Air Cooler. ✔ 1 × Portable 15L Air Cooler. ⭐ Large 15L water tank for longer cooling. The advanced waterfall cooling technology uses water evaporation to transform warm, dry air into a refreshing cool breeze while helping maintain a comfortable indoor atmosphere.