*Each retail box has 1 stick, and each stick can filter up to 3-5 gallon water. Instruction is below. Binchotan is the highest grade of charcoal from Japan. Each Binchotan stick is carefully made by craftsmen in the Kishu region. It absorbs odor, reduces water hardness, and improves the overall taste of water. Instruction: - First use: rinse with water and boil for 10 minutes and let dry. - Filtering time is 9-10 hours. - Reactivate charcoal every two weeks by boiling for 10 minutes and letting dry. - Each stick can be used for about three months. After that, it can be broken into pieces and used as a natural deodorizer, or recycled in plant soil. - Do not use with water that is microbiologically unsafe or of unknown quality.