Easy to use Mini Drain Design: The drain water generated when the spot cooler is running will gradually accumulate in the drain tank with continuous use. Once it is full, you must replace the drain tank.In response to the saying that "drain tank is hard to replace heavy", we adopted a mini drain (3L) that can be easily removed and compact. Compact Mini Type: Easy to move with casters (All sheet metal body) Heavy duty and impact resistant all sheet metal exterior that can withstand harsh sites. Dust switch: Dustproof switch to guard against dust and dust intrusion. (Front air filter is adopted) Easy to remove and maintain.