3 wick cooker candle in a can will boil 1/2 liter of water in 15 minutes as well as being used for light. You can use the candle for 12 hours if you are burning all three wicks at the same time for cooking. If you use one wick at a time and rotate burning the wicks, it will burn 50 hours for light. The candle is sealed in a 4" x 2" can with matches sealed inside so it is ready when you need it, and it also comes with a snap on plastic lid. The can is enameled inside and out for rust prevention. Can will not break, it's waterproof and oil will not leak. It's low and wide center of gravity so does not fall over and will last forever on a shelf.