Ender 3 Pro fan silencer
thingiverse
I remixed this to fit over the Meanwell power supply unit on an Ender 3 Pro. It still has the screw holes but I installed it with double-sided tape straight over the fan inlet to reduce the noise some. PLA, PETG, or ABS could be used. It's not going to completely quiet the fan but it will reduce some of the turbulence noise.
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