PowerChill Thermo-Electric Cooler with Adjustable Shelf
[3000001497]

Perfect. Affordable and effective. Keeps food and driks cold all weekend without using ice. I load it up with already cold items. Then keep it in the shade where the breeze is and only open it when necessary without keeping the door open longer than necessary. I plug it into the 12 volt outlet for about two hours at a time throughout the day. I've not had a dead battery and all of my food stays well.