Amazon.com: MakerFocus 3D Printer Fan 24V 4010: 4pcs 3D Printer Cooling Fan 40mm Quiet 0.08A DC Mini Silent Brushless Fan 2 pin for 3D Printer, DVR and Other Small Appliances Series Repair
STL file Sprite/Sprite Pro Silent Cooling Duct w/ Noctua 40mm Fan・3D print object to download・Cults
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Scythe SY124010L Mini KAZE 40mm Silent Case Fan - Walmart.com