USB Desktop Fan, Double Blades Mini Portable Fan Super Mute Table Fan Personal Fan Laptop PC USB Cooler Small Fan Adjustable Angle (Black) USB Power Supply: with a a standard 5V USB port, you can connect the fan with a power bank, laptop or any other usb power adapter. Portable and Quiet Design: adopting ultra quiet motors, the fan produces noise below 40dB while working. Mini size and lightweight, suitable for home and office. Collapsible: Twist the cover anticlockwise to open the fan for cleaning. Long-Lasting Life: up to 1400 hours life time of motors. Double Motor/Blades: two fan blades rotate in opposite directions driven by different motors to produce powerful breeze with low noise. Angle Adjustable Blow Direction: the fan can be adjusted from 0 to 30 vertically. Two working modes: 1-Weak, 2-Strong.