This is a battery door that fits GoPro Hero 9 through 12. Designed so that you can plug in a USB cable while the door is closed. I have personally tested with Hero 10 and others have posted makes showing it is working with Hero 9-12.
Make sure to print it on it's side so no supports are needed.
I've included a STEP file so you can easily edit in your own CAD software.
The author marked this model as their own original creation.