Review on 🔥 Black 4-Set EasyCargo Raspberry Pi 4 Cooling Fan – 30x30x7mm, Brushless 3.3V 5V DC Fan – Compatible with Raspberry Pi 4B, Pi 3B+, RetroFlag NESPI Case (30mmx30mmx7mm) by Gabe Smith

These are pretty decent quiet fans with acceptable airflow to keep the Raspberry Pi cool. everything so I returned them and bought these instead. Tip 1: These fans are not designed to run 24/7 and the more you use them the quicker they die. Get dual ball bearing fans if you need 24/7 airflow. Tip 2: If you're using on a Raspberry Pi, consider controlling the fan via software/script as you don't technically need to run the fan 24/7. Google "raspberry pi temperature controlled fan" to learn how to toggle the switch OR you can buy a pre-made super small fan from tindie.com made by YouTuber Jeremy S. Cook (check out his video to see how it is). I like it, he designed the circuit himself (shown in his video). I also made some of these myself, but I had to buy lower resistors so mine wouldn't work with fans that require more power. So I use my build in Pi3 and 2 Jeremy builds in 2 Pi4s (ice tower and on top of the passively cooled case). this keeps my pis cool all year round and the fans don't run in the winter and come on every now and then in the warmer months but more often in the summer.