A 10-inch rack mountable shelf for rack! It comes in two variants. One with a slots pattern, and another with a hex pattern.
This model is part of a series of 10-inch rack mounts I've designed. You can check out the others here.
I have added a .3MF project file as well.
If you're slicing the model yourself, I recommend you to print in the following orientation for better strength:

Rafts:
Doesn't Matter.
Supports:
No.
Resolution:
0.2 or 0.24
Infill:
20% or more
Filament:
Any.
The author marked this model as their own original creation.