Review on 🌀 ANVISION 2-Pack 40mm x 10mm DC 5V USB Brushless Cooling Fan with Dual Ball Bearing Design - YDM4010B05 by Logan Tripp

I bought this to cool the 20Amp solar charge controller - it plugs directly into the charge controller's USB port. It seems to work to keep the charge controller cool - the real test would be on a very sunny day - the last few days have been mostly cloudy. The fan is about 1.5 inches square and makes a noise that I can hear from about 10 feet away. By placing your hand on the bottom of the charge controller (it's mounted on the board and raised about half an inch above the surface). ) I did feel a breeze from the fan, but the only way I can install it is by pressing it against the charge controller so that only half the airflow is past the charge controller.