Material: Candle wicks are pre-coated with paraffin wax and made of natural cotton thread, free of lead, zinc, and other metals. Smokeless and odorless: Well-made wicks produce no black smoke or smell and burn steadily when lit. Easy to cut: Wicks can be easily trimmed to the desired size, remain intact, and are suitable for candle making and DIY candle projects. Application: Simply attach the wick to the bottom of the container and center it using a wick centering tool while pouring wax. Features and performance: Well-constructed wicks provide even burning with no black smoke or unpleasant odor. Detailed data: Natural white cotton wicks, 20 cm in length; includes wick base measuring 0.79 inch (2 cm); wick centering device measures 9.5 cm in length. Note: 1. Due to differences in monitor displays, the picture may not reflect the actual color of the item. 2. Due to manual measurement, there may be a 12 mm error.