20 Hours Max Cooling Time: Equipped with a larger 4000mAh battery capacity, twice as large as others, which supports 20 hours max working time with a full one depending on the wind level Portable Desk Fan: This mini fan can be used as a handheld fan outdoors and a mini desk fan on a flat table in the office; The base is equipped with a non-slip pad to keep it stable. USB Rechargeable: JISULIFE mini hand fan is USB rechargeable with only 3 hours to fully charge; It supports USB charging by USB charger, car charger or computer. Easy Cleaning & Mini Size: Featuring a removable cover, this mini handheld fan is easy to clean by turning the cover and fan counterclockwise to separate; Besides, it is small in size for convenient carrying in your bag. Tips: Before using or charging, turn on the anti-trip switch under the base; One-button design: short press to turn on the fan, then press repeatedly to adjust the wind speed or turn off the fan