On a Duraflame fireplace log: “Caution—Risk of Fire.”

On a Batman costume: “Warning: Cape does not enable user to fly.”

On a bottle of hair coloring: “Do not use as an ice cream topping.”

On a cardboard sun shield for a car: “Do not drive with sun shield in place.”

On a portable stroller: “Caution: Remove infant before folding for storage.”
If you have any good ones, please add them as comments…