I was a bit annoyed from Tesla removing the original cup holder cinches as discussed in this thread (Cup holder cinchers). So I did some testing and found that the rubber inserts from a Chevy Trailblazer will fit and somewhat aid in not letting your bottles tip and move. Both inserts fit within the upholders and can be installed and removed easily. There is about 1 inch of room after installation between the inserts and the top of the cup holder so the arm rests can still slide to cover the area. If you do a google search for "DDD23949", you should find the part from GM. I ordered my set from eBay and it came with 2 small inserts shown in the picture and a large insert that is useless. Wasn't sure if these would fit when I ordered but they seem to work great. Perhaps if anyone ordered from GM, they can only get the small ones.