The NF-A20 5V PWM is a quiet 200 mm premium fan with a square AAO (Advanced Acoustic Optimization) frame. Thanks to its 4-pin PWM connector, the fan speed can be regulated and ranges from 350 to 800 RPM. Due to the 5V specification, it is not suitable for operation on motherboard headers. However, the fan can be powered using a USB adapter with USB power supplies and smartphone power banks. With the OmniJoin adapter set and the integrated reverse polarity protection, it is also possible to safely install the fan in many devices with proprietary fan connectors.