I have those freezer packs you get when ordering meat online. roughly 8 x10". I thaw these and then ck for leaks. Those that leak are recycled. I have prob a dozen or more. I use these to fill the vacant spots in my freezer. In case of a power outage these will keep things cold for way longer. and while not recommended, I put a thawed one in the freezer and take it out b4 it freezes and then use it to cool my aching knees.