I use these ice packs. They’re amazing! I’ve had them for over two years and they work so well! I put one in my lunch box with two room temperature drinks and it actually COOLS the drink to fridge temp within two hours. So you can imagine how good it is when things are already cold. I also use this lunchbox and I’ve recommended it to so many people. I read a lot of reviews before I bought it, it’s held up so well and I really stand by it. I like that it has two compartments too so if you don’t want everything to be good you can put warm/room temp things in the other section.