Review on Raspberry Pi 4 Fan Quite: 4Pcs DC Brushless Cooling Fan 30Mm LED Heatsink Cooler Radiator Connector Separating 1 To 2 Interface 3 by Bart Schwalbe

These are decent little fans for the price, I wish they would last a little longer and stay quiet longer as other reviews have mentioned that some fans are fast and getting quite noisy can only occasionally be eliminated by adding oil. Build quality is good overall and they last six months to a year on a 12 hour cycle at around 100F and maybe just over 100F (I use them to cool a device I've modified and I also used them with medium power LEDs with small heatsink)