I bought this for an off-grid camping trip in very warm weather. I filled it the bottom with canned beverages and food and put ten pounds of cubed ice over the top. I didn't pre-cool it or the beverages. The food was frozen, however. I kept the cooler out of the sun and tried to only open it 3-4 times per day. After 5 days, the cooler contained about half ice and half water.  Very impressive for such a value-priced cooler!