If you really want your stuff to last a long time, put about 2 inches of news paper on the top of the ice. On cold nites, the ice will actually re-freeze. When we go up in the BWCA, we'll get an extra 3 dyas out of ice that we used the newspaper on. Make sure to pack out the paper when your done. Makes for OK back up butt wipe in a bad pinch.
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The best way to be succesful in life is to keep the people who hate you away from the people who are undecided