Easycargo 40mm USB Fan, Cooling USB Mini Small Cooling Fan 5V DC 40x40x10mm Quite 4010 (2-Pack)

I bought this to cool down my router. It does the job; it's very powerful for its size but it is a bit noisy (not a quiet fan as it's advertised). It comes packaged with two fan grills each (so a total of four grills for two fans), so you can put them on both sides if you want. The screws although it works for its purpose, it was way too long.Overall, if you want a cheap fan for simple project, this will do. It's quite powerful but keep in mind that it's a bit noisy.

Used a couple dots of glue to add this to the back of a tablet with a failed fan while waiting for repair. Worked great.One fan seemed a little off balance and noisy, but still worked.

Wow these things can move air. Quick shipping and good quality. Time will tell about reliability. Would buy again

I'm generally quite happy with these fans. They cool my UAD Apollo Twin Quad down noticeably. However, they are noisy, so I use them only when wearing headphones.