These are the most amazing fans for their tiny size (40mm) 5,000RPM at 3,500 RPM silent : r/Noctua
NF-P12 REDUX 12V 900RPM 120mm Quiet Case Fan
High Quality Noctua NF A4x10 FLX 40mm 12V 5V 40X40X10 Cooling Fan 4010 Silent Cooler Fan Radiator 3D Printer Parts for ENDER 3|3D Printer Parts & Accessories| - AliExpress
Noctua 40MM 3700RPM SSO2 Bearing A-Series Blades Fan
Help painting/dye Noctua 40mm fan... what method works best? : r/sffpc
I added these two Noctua 40mm fans to the rear of my case to provide additional cool air intake for the voracious 2080Ti FE : r/nvidia
High Quality Noctua NF A4x10 FLX 40mm 12V 5V 40X40X10 Cooling Fan 4010 Silent Cooler Fan Radiator 3D Printer Parts for ENDER 3|3D Printer Parts & Accessories| - AliExpress