These are the ORIGINAL Hot Cold Bags; 100% recyclable, food safe, reusable. They offer a convenient way of keeping items hot or cold and frozen for hours at a time. Since they are so light weight and fold completely flat you can practically take them anywhere, or keep a few of them in the trunk of your car so you are always prepared. Great for any activity including grocery shopping, the beach, boating, fishing, sporting events, lunches, picnics, travel, etc. Don't waste your energy carrying around a bulky cooler. Less is more! NOTE: Sometimes shoppers are surprised at the size of the grocery bag, please be aware it is a BIG BAG (18"x18")! If you would like a smaller bag please make sure to select the lunch size