This ultra clean white burner sand is excellent and should be used in all non-screen burners. Add a good amount of this sand in the bottom of your vessel and it allows your coal disc to burn all the way down and acts as a heat sink. This means it absorbs the heat from the coal and allows the vessel to stay much cooler. With this sand under your coal you are also able to safely use stone, clay and ceramic non-screen burners. Each 3 inch bag contains enough sand for 2 to 3 burner fills and should be changed periodically as needed.