Amazing to find a product that me my needs. Its a good start to a design concept and just what I need to endure the trip to the amusement park on a hot day. During every long line in the heat, I sat down and pulled out an ice cold drink from my cooler. outside pocket is very helpful for wipes, utensils etc. drink colder needs to expand to fit today's tumblers (longer and a bit wider). Unfortunately its very uncomfortable as the metal bars dig into the back of your thigh and restrictricts blood flow. Im 145lbs. The seat ripped slightly on the first use and the straps dont help it close properly when switching to back pack mode. If you redesign with stronger seams at the stress points and add padding, I would rebuy. As is, it would be best suited for a toddler-8yr old to sit on it. Cooler kept my items cold for 5hrs. I would be happy to test any of your future designs.