40mm USB Fan USB Ventilator 5V Cooling Fan Compatible for phone flat VR Gear, Aquarium, Roku, Router, Raspberry Pi, Cosplay, Helmet Receiver DVR Playstation Xbox Computer Cabinet Cooling

I am using to keep my Thunderbolt 4 hub cool during heavy load on the T4 hub. I like that the fan comes with two different ferrrous tape backed plate/ring so the fan stays put with its magnetic feet. I also like that it is USB powered and has three speed settings. High seems a little loud, but not louder than my computer's internal fan, so it's fine, plus I normally just keep it on low which makes little noise. It's been perfect for my application.

Slow speed moves too much air so is noisy. I am going to change the resisters to adjust. Just need a little flow. The 1" I tried was enough but needed the larger form factor to fit the heat sink.

Made of nice material and lightweight, it's not very strong but enough to cool one IT component such as a router. USB interface is a plus. Very silent. 6 months in continuous use, still doing well. Good value for the money.

Use this fan to prevent GoPro cameras and other digital cameras from overheating when recording 4k in high frame and bit rates. Quiet enough on low and medium settings that it cannot be heard on video. Can be heard on highest setting, but only in the setting of a quiet room. Otherwise, works like a charm!

Just terrible quality…

This worked very well to keep a Raspberry Pi cool. Because of were the Pi set up I cannot do a case with fan and this solved the problem. The magnets do hold but will come off with the slightest tug so be aware of that. As for noise it seems a bit to the loud side even on low but is noisy on high.

it works as intended although the fan does get a bit loud at the highest setting

Bought two. Both unfortunately stopped working in the span of two days.