Black+Blum Charcoal Water Filter - 4 Pack From the successful Charcoal Filter Range by Black+Blum, Binchotan active charcoal is used to filter water by absorbing impurities such as chlorine. It has been used by the Japanese for over 500 years and will make your tap water taste great. This range was created to encourage people to stop buying expensive bottled water and adding to the continuing single-use plastic global environmental problem. These charcoal refills are pre-washed and vacuum sealed so they are ready for immediate use. Simply drop the charcoal into your water, we recommend one stick per litre, then leave for 1 hour (8 is best) and enjoy your filtered water. Each charcoal will last for 6 months as a water filter, simply recharge after the first 3 months use. They are then recyclable for other uses around the home. They fit in Eau Good, Eau Good Glass, Eau Carafe and all Box Appetit water bottles but can also be used in any jug or bottle. About Black+Blum Black+Blum are award-winning producers of original, sustainable products that people love to use every day and are proud to own. They endeavour to create objects of enduring value and practicality that age well and are built to last.. Dan Black and Martin Blum are passionate about sustainability and doing their part to protect the environment. They have an eclectic taste and this shows through the varying aesthetics of their individual products. They design in-house but also collaborate with the most talented designers worldwide to bring the finest lunch boxes and water bottles to the market. From the successful Charcoal Filter Range by Black+Blum, Binchotan active charcoal is used to filter water by absorbing impurities such as chlorine. It has been used by the Japanese for over 500 years and will make your tap water taste great.