Fast Charging: The fan built-in 4000mAh batteries which support fast charging, it will work continuously for 4.5-40 hours after 4 hours full charge with 5V/2A input. Adjustable Oscillation: 360° manual vertical and horizontal rotation allows you to freely adjust the wind direction, 80° automatic oscillation provides comprehensive coverage, feel cool from any angle. Three Speeds: Low speed, natural and powerful. Fan speed adjustment allows you to adjust the wind speed to the most comfortable level. USB or Battery Powered: The fan is battery powered and compatible with USB charging adapter, power source, laptop, etc. etc. It is convenient to use indoors and outdoors! Compact Size: With 2-in-1 design, our desk fan has aromatherapy function. You can add essential oils to give your summer a different taste. It is lightweight and portable (21 x 15 cm), perfect for stroller, home, office, camping, travel, etc.