-100% natural cotton, contains no lead, zinc or other metals. -Low smoke and burning stability when lit. -Works with most kind of wax (soy, paraffin, beeswax, palm wax, melted butter etc.), can be used in most types of candle projects. -Can be used with a wide variety of candle wax containers, such as: soda/soup cans, jelly jars, tea cups, coffee mugs, sea shells, bowls, plant pots, etc.