This is are screw down tabs to mount a Mean Well LRS-350-24 power supply. It holds the PSU from the side and allows you to fix the PSU from the top.
I recommend you use 4 tabs to mount the PSU.
This design is part of my frame, bracket and holder collection for various boards and components: https://www.printables.com/@a123qwertz567/collections/2632544
I would be happy to see some of your makes posted :)
Source files in the Alibre Atom format is available but the website does not allow the upload. If you need it send me a message.
The author marked this model as their own original creation.