4PCS Quiet Silent Cooling Fan 12V 40mm Fan 0.08A DC for 3D Printer DVR Repair US | eBay
Noctua NF-A4x10 5V Quiet Cooling Fan 40mm
Nidec UltraFlo Ultra Silent 40mm 4015 Fan (3500RPM 16dBA) - MODDIY
For Delta Efb0412la 4cm Best Silent Quiet 40mm Fan 4010 12v 0.08a Cpu Computer Inverter Cooling Axial Cooler - Pc Components Cooling & Tools - AliExpress
blacknoise.com - Noiseblocker NB BlackSilentFan 40mm
Amazon.com: Gelid Solutions Silent 4 – 40mm Computer Fan, 3 Pin Molex, 40x40x10mm, Fan Speed: 4200RPM, Hydro Bearing, FN-SX04-42, Very Quiet, Noise Level 18.9 dBA, Color Black : Electronics
4Pcs 24V 40mm Cooling Case Fan 4010 40x40x10mm DC Mini Silent 3D Printer 2-Pin | Being Patient
Amazon.com: AABCOOLING Super Silent Fan 4 - Silent and Efficient 40mm Fan with 4 Anti-Vibration Pads - Value Pack 3 Pieces, 12V, Quiet Fan, 3D Printer Fan, Silent Case Fan : Electronics