The bag for almost all your needs. There are so many uses, limited only by one's imagination. From the easy-to-load Wide Mouth, flat bottoms for stability, straps completely around each bag for strength, THICK insulation (including the dividers) for thermal uses, and water-repellency to the easy-care washability, these bags are so versatile. Use the Mini size for lunches, makeup, toiletries, medication. Then there's the Regular size useful as a dual purpose bag--pack a lunch on one side and purse on the other -- one bag, two uses. The Maxi is incredible as a sports bag, diaper bag, gym bag, luggage. And the ultimate Super-Maxi is great for luggage (it is airline-legal as a carryon), beach bag, craft bag, sewing machine bag, pet carrier. And storage is a breeze as the Super-Maxi holds all the others. These Wide Mouth Bags are truly amazing!