I know a car cup holder adapter that allows you to insert your Hydro Flask or Gatorade bottle without it flying out of the console every time you stop, turn, speed up, or slow down won't change the world, or even your own life all that much, but I still think it's a nice 21st century amenity to have. Right up there with Hydro Flasks and Gatorade themselves. The Bottle Pro base is designed to fit snugly into a wide variety of narrow car cup holders, while its blooming mouth opens up wide to accommodate big ass bottles 3.5" to 3.8" in diameter. In addition to the above, these include 32-ounce Nalgenes and 40-ounce Kleen Kanteens. The Bottle Pro also has a 1" opening on its side so that handles on travel/coffee mugs slide in easily too.
Bottle Pro cup holder expanders are made of rigid plastic intended to hold up well both to the bottles they holster, and the extreme temperatures vehicles might experience.