Bottom part (the one that fits in the car's cup holder):
Top part (the one you put the mug/cup in):
It does not fit snugly in the car's cup holder. It prevents the top from falling out or wobling.
Nor does the mug fit snugly in the adapter - its easy to take out and put it, but still holds it from falling or wobling.
Printed at 0.28 layer height in PETG (car gets hot). You need support for the brim of the top part.
Tested in Renault Megane 2020 and Geely Geometry C cars.
The author marked this model as their own original creation.