This charcoal stick is all you need to makes tap water taste great! Binchotan active charcoal has been used in Japan as a water purifier since the 17th century. It may seem counterintuitive to purify your drinking water with a stick of charcoal, but binchotanan active carbon made from tree branches is renowned for its ability to soften water, add good minerals and absorb unwanted tastes and odors, such as chlorine. This set includes a metal coil you pop the charcoal into, so that you can have filtered water in almost any type of water bottle. The coil locks it in place so the filter won't knock around inside the bottle.   What's it made of? Binchotan active charcoal filter (6 months life) and metal (the coil)   How does it come?In a cardboard box.