冰袋（保冷箱）

This ice pack slides perfectly into my lunchbox without taking up too much space, and I love that there are two sizes to choose from. It keeps my drinks cold all afternoon, even on hot days.

I was skeptical about how well it would fit in my lunchbox, but the slim profile slides right into the side pocket with room to spare. After a few hours in my bag, my drinks were still noticeably cold—way better than my old ice packs that would be lukewarm by lunch.