Filtration up to 1 Micron: To ensure excellent filtration performance, this filter element uses premium coconut shell activated carbon as the filtering material, offering a filtration precision of 1 micron. It efficiently removes various impurities such as sand, rust, sediment, bad taste, and effectively absorbs residual chlorine with a removal rate of over 99%Compatible Models:Black water filter, replacement for BB9-2 water filter. Compatible with Berkey Gravity Filter Systems, including Travel, Big, Royal, Imperial, and Crown Series. The precise design of the washer and wing nut ensures a firm connection to prevent leakage. No priming is required; replacements can be installed and used immediately, saving time on early flushing. No issues with low flow ratesMaterials Certified for S.a.f.e.t.y: The water filter uses natural filter materials and a premium drilled carbon sintering process, certified by NSF/ANSI 42 to ensure a s.a.f.e water experience for your family. No need to worry about contaminants or strange odors leaching back into the waterNote!: Before installing the filter, soak and clean it to remove residual manufacturing dust. The primary function of water filters is to enhance the taste and quality of water, rather than specifically reducing the total dissolved solids (TDS) content in the waterDurable Lifespan: To extend the life of your equipment and ensure optimal performance, we recommend replacing the filter every 6,000 gallons (depending on the quality of the tap water being filtered). Please note that the carbon filter must be completely submerged about once a week for the drip system to siphon properlyWood