Binchotan has been used in Japan since the 17th century to purify water. The ions from the pollutants in the water are attracted to the surface of the carbon and are retained here. Binchotan can also release various minerals into the water, enhancing its taste and health benefits. This is why the Binchotan is also known as 'active carbon'. The Binchotan lasts for 3 months and then can be recycled as fuel for the BBQ. Before use, the Binchotan must be boiled up briefly. Binchotan can be used in a variety of drinking bottles and water carafes. This product contains 1 piece of Binchotan.