Fan Light Sound USB Charging Fan Student Office Home 4000mAh Features: Battery and USB charging fan: The fan has a built-in battery power supply and USB charging fan, with a built-in 4000mAh battery. It has a long working time and is a portable fan suitable for camping, travel, and other work. You can also plug it into a power source to work continuously. Super Silent Fan: Unique upgraded blade design. The minimum noise of this desk fan is close to 36dB. This mini fan is quiet enough, but still strong enough to bring cool wind and provide you with a comfortable working environment. The perfect choice for work and study. 5-level adjustable wind speed and low voice: The speed of this desktop built-in battery fan can also be adjusted between 5 level according to your needs. It is generous and quiet, ensuring a calm motion of gas that is sufficient to meet needs. Packaging content and customer service: You will receive a built-in battery fan and a USB cable. Brushless motor and 8-inch fan blades: Brushless motor has a lower sound airflow. The 8-inch fan blades will bring more wind to you, with a gentle feel and no headache even after blowing for a long time. 4-30 hours of battery life: The fan is equipped with a large 4000mAh battery, which has a battery life of over 4 hours. Using a single layer, the usage time can 8 hours. If two are used simultaneously, the usage time is also 4 hours. The double-layer design can be used by two people simultaneously: traditional shaking head fans waste a lot of wind, while double-layer fans can be used by two people simultaneously to avoid wasting wind. The double-layer fan can be adjusted at 350 degrees: the angle of the double-layer fan can be adjusted to 350 degrees. Product Description: Fan blade size: 10.49 inches Speed regulation: 5th gear Battery: 4000mA Motor type: Brushless motor Fan blade material: plastic Noise: below 37dB Power: 10W Voltage: 5V Range: 4-30 hours Size: 6.49 * 5.31 * 15.35in Including: Double layer fan * 1, charging cable * 1 Small Table Fan Mini Portable Tower Fan Adjustable Quiet Desktop Fan USB Fan for Office Dorm USB Clip-On Fan for Home Office and Outdoor Cool Needs Hanging Charging Portable Outdoor Neck Fan Brushless Silent Fan Desktop Fan USB Rechargeable Office Outdoor Camping Portable Handheld Fan