I’ve purchased 4 and thrown away 3 because of leak’s. I’m a very careful adult and no one else uses it. They rip in my lunch bag that they were specifically made for .Used these for flying with breast milk. Kept my milk frozen and TSA had no issues.I bought these to travel with my breast milk on an international flight from Los Angeles to London. When they arrived, I was disappointed to see how flimsy, small and cheap the ice packs were for the cost ($15+) but decided to keep them to use in addition to my larger Medela ice packs. At LAX airport security these icepacks were promptly confiscated by the TSA as they were "not completely frozen". I argued that it shouldn't matter since of course they had been previously frozen and were there in the service of the breast milk, which is exempt from the liquids rule for carry on luggage. The TSA agents ignored all of this and took these smaller ice packs. They let me keep the Medela packs as according to them, they were "still frozen". Disappointing and a waste to have traveled with them - beware!Last a long timeThis ice pack is useful for chilling pumped milk and bottles etc. when used in small insulated bag with ice pack pockets. I have no problems with the product itself, it works as it should. My only dislike is the price, I think it was too much for what you get.Freeze nice and solid, with a good insulated bag those will start frozen for most of the day!I bought these for my sons school lunches, I think he accidentally zipped it up in the zipper of his lunch bag and it punctured a decent sized hole in it, we had to throw it away after just 1 use. I gave it a 4 because I think it was partially his fault :/These stay frozen for what seems forever! You have to be careful though, sometimes if I put in 3 of them then the stuff in my cooler pack will start to freeze. They do let off a lot of condensation, but I use them with the same brand 3 bottle cooler which doesn't let the condensation leak through. I have never found anything better, the size and quality and price are just right with these.Para poder ingresar este tipo de producto (líquidos) me pidieron que me inscribiera al patrón de importadores, cosa que no pude hacer, así que tuve que mandar carta de abandono para que me pudieran liberar el resto de mi paquete.Ive purchased two boxes and one came with my bottle bag, ALL of them broke open within 2-3 weeks and leaked everywhere. I was very disappointed considering the price. I do not recommend and would give it -5 stars if I could!!