Alfawise U20/U30 Fan Insert for 5mm LEDs

This is a tiny 3mm thing to place between 4cm fan and the red plate instead of the white "spacers".

The exact DC converter used was https://www.aliexpress.com/item/Power-Supply-Module-Replace-LM2596s-Mini-3A-DC-DC-Converter-Adjustable-Step-down-Power-Module-Hot/32955086004.html but you could adapt to a model with all the wires on one side...

Made for 2 5mm LEDs...

Tip: you can wire your 3cm fan to the output of this DC-DC module to reduce the noise...