Well. It's one of the few products that I've bought, that actually does what it promises!!! In my case it's Wonderfull because I drink a lot of Pepsi Max because I like the fizz. But I by cans, because I dont drink that much at a time, and then the fizz quickly dies out and I end up pouring 1 L Pepsi Max out... BUT! My Chilly's bottle is not only keeping my Pepsi ICE cold forever, IT KEEPS THE FIZZ IN THE DRINK!! So now I can actually save some bucks on buying bigger Pepsi's because a 1,5 L pepsi only needs to be opened 3 times (1,5/0,5) so the fizz doesn't die, AND my Chilly's bottle keeps it cool with me on the couch all day AND night long! I will be buying one more for sure! Just wish a 1 L bottle was available...