A hook that clips onto a drink bottle, to hang it somewhere.
I was fed up with bottles always rolling around on the passenger side floor of the car, so i just hanged it onto the shelf in the middle. Just clip it onto the bottle and you're done.
Fits standard water or coke bottles in germany. Not sure if the diameter standard is international though.
I recent found out it also works on airline seats.
Built with support (automatic, by cura), otherwise the hook end wouldn't be possible i think. Holds 2L Bottles with 20% infil just nice, if you need to hang a gallon or break it, use more.