This is a simple design that can print without any supports. The resulting tapered cylinder should fit into the secondary drink holder that slides under the open armrest of a 2009-2015 Prius (I specifically drive the 2011).
At minimum you should print this with PETG. The one pictured (that I've kept in my car since May 2022) was printed with Prusament PETG and has held up nicely in Texas temperatures up to 105*F. Some will claim that you must use ASA or other material with higher temp resistance. I assume no responsibility if your print melts or damages your car.
Print with narrower cylinder on the bed
Prusament PETG
0.30mm Draft print setting
Perimeters: 4
15% Grid infill
Nozzle temp: 220/220
Bed temp: 85 first / 90 other
I've also uploaded the STEP file should folks want to remix.
The author marked this model as their own original creation.