This is a complete case for the Geekworm PiKVM-A4 that includes the CSI, ATX and OLED modules. The top of the case is press fit onto the bottom half. You'll also notice there is a rise for 2 of the standoffs due to the manufacturer providing standoffs for half of the design that are 2mm too short.
Geekworm link: https://geekworm.com/products/pikvm-a4
The author marked this model as their own original creation.