Chitu Systems Resin 3D Printer Mini Heater-Versatile Temperature Control Heater Support.
You need 4 M3x4 hot inserts and 4 M3x10 screws.
First pass the cable through the two pieces, fix everything to the cover and finally position the heating cartridge.
I printed on PC but I think PETG is fine. I don't recommend printing in PLA.
The advantage of this holder is that the air flow is not directed towards objects.
https://www.amazon.it/dp/B0C3VTHSZ6?psc=1&ref=ppx_yo2ov_dt_b_product_details
The author marked this model as their own original creation.