2pcs Raspberry Pi 3 Model B Fan 30x30x7mm Raspberry Pi Brushless Cooling Fan Brushless 3.3V 5V DC Quiet Fan for Raspberry Pi 3 B+, Pi 3 B, Pi 2, Pi B+, Pi Zero/Zero W,Robot Project

I had a RPI4 kit from “LABISTS” and the fan that came with that was horrible. Very loud.Got this one, it’s much quieter and does a fairly good job cooling. In another RPI4 I am seeing about 50 degrees celsius; with this fan in the other RPI4 I see about 55 degrees celsius. It doesn’t cool as much but it is quieter, so I think that is fine for this unit.I think the secret is that this fan is about 1/2 as deep/tall as usual RPI fans I have owned. It fits in the same space but since there isn’t as much surface area, the fan doesn’t cool as much (and the fan doesn’t make as much noise). If you have a big need for the most cooling, this isn’t the best option. But if you prioritize quiet as your #1 criterion then this is a great pick. I am very happy with it. Only had it 1 day but so far it’s been great.

These unlike many others by other manufacturers work great and are actually quiet! Most claim to be but these are.

It works well and does blow air. It doesn't blow a lot of CRM but this is a 30mm fan running at 5v. It brought my Raspberry Pi 3B+ down from 49*C to 33*C while using a heatsink with this fan. It's not whisper quiet but next to my Ender 3 V2 running Klipper and 200m/s, you can't hear it over the machine. You can't ask much more for a 30x30mm 5v fan.

These fans are small and quiet. With 5V (max) you cannot hear them. They do not move much air so don't expect high mass airflow.

Works great, I used then to replace the fans on my traxxas esc that keep going bad.