Review on 💨 ELUTENG 40mm USB Fan: Powerful 3-Speed Control Ventilator for VR, PS, Xbox, PC Cabinet Cooling by Chris Meckler

This variable speed fan with on/off switch for High, M, Low on the cord is just what I needed. My NAS has two mSATA cards that attach to the back of the motherboard where there is no airflow inside the case and they get very hot. So I cut a round hole in the metal cover, attached a 4.5" speaker grill to the hole, and attached this slim fan directly to the speaker grill with small screws and rubber O-rings (see image). mSATA drives remain in good condition. and cool, and this fan is not at all audible on low settings. In fact, I can't hear it at altitude when the case fans are running. PERFECT for my needs.