This model is a power supply cover for the Ender 3 - V2. The cover supports the low profile Noctua 14mm fan, NF-A9x14. 
link: https://noctua.at/en/products/fan/nf-a9x14-pwm
Usually, this part is meant to reduce the noise level.
on the back I have added a Cable holder for the backside cabels.

I recommend printing it in a higher temperature-resistant filament, especially if you are printing inside an enclosure.