This is a small clip designed to attach to a charging cable and hold a silicone USB C dust cover while a smartphone charges.
Silicone dust covers are a great way of preventing dust from getting into your device's USB port while it is in your pocket, etc. Unfortunately, they are small and can be easily lost when it is time to charge your phone. This clip keeps it close by and provides a visual reminder to replace it when the phone is done charging.
This version was designed to fit a cable with a diameter of 3.5 mm. The original CAD file (Fusion 360) is included you need to adjust the size to a different cable diameter. The dust cover I used was from Amazon (i.e., https://www.amazon.ca/gp/product/B08BKKDR59 ), but since it is sized the same as the USB port, other versions should work just as well.
The author hasn't provided the model origin yet.