Anyone using Polar Bear tubes?

I take a 9x13 cake pan and freeze blocks of water then i set some on the bottom and some on end around the cooler walls.. They pop out of the metal pan pretty easy. I throw some Ice cubes from the home freezer over the top of the pop and water bottles.I also put a sheet of aluminum foil in the bottom of our cooler . It sits outside the camper door and I throw an old throw blanket over it. It helps keep the cold in as well.. Works for us..