I found that the dual cupholder in my Rav4 is a little loose for my Dopper water bottle. So I tried 3d designing for the first time, to solve my problem. Turned out pretty decent! The asymmetrical and conical cup holder was not an easy starting point, but we managed it! The ring also works great for energy drinks, like the RedBull can.

The model was created in Fusion 360 after some reference photo's.