This is a protective cap for DJI Osmo Action's port slot with a USB-C cutout which lets you to charge the camera while protecting the port from the weather.
Usage:
I have designed this to fit USB-C connectors with 12.2 mm width, 6.4 mm height dimensions (=these are the dimensions of my standard Logitech USB-C cable connector) but you can change these values in the design parameters.
Link to the Autodesk Fusion 360 design: https://a360.co/2D5lGYG
The author marked this model as their own original creation.