【Compatible Models】 Direct replacement for Berkey PF-2 filters, compatible with Travel, Big, Royal, Imperial, Light, and Crown Berkey models. Also functions as an additional filter for Purewell gravity water systems. Precision-engineered for perfect fit with zero leakage, seamlessly connects with Berkey BB9-2, as well as Purewell's black activated carbon and ceramic filter elements (Note: Purewell is an independent brand - not sourced or sponsored by Berkey). 【NSF-Certified 5-Stage Filtration】 Certified to NSF/ANSI 42 standards with high-performance 5-stage filtration technology. Combines a fluoride reduction membrane, activated carbon block, and three sediment PP membranes to effectively reduce fluoride, chlorine, and impurities for cleaner, safer drinking water. Note: The Purewell fluoride filter (white) cannot decrease Total Dissolved Solids (TDS). 【90% Fluoride Reduction】 The Purewell Fluoride Filter is made from advanced fluoride removal material. Unlike traditional alumina-based filters (which can pose health risks), our fluoride filter uses a safer, more advanced filtration media to remove up to 90% of fluoride. Plus, it's NSF/ANSI 372 lead-free certified, so you never have to worry about harmful leaks or contaminants. 【Long-Lasting & Replaceable】 Provides up to 2,000 gallons of filtered water (single element lifespan: approximately 500 gallons; varies by water quality). For optimum performance, replace Purewell FL-2 Fluoride Reduction Elements at 2,000 gallons under normal operating conditions. 【Hassle-free Purchase】 For optimal performance, pre-prime your filter (as instructed in the manual). If you experience clogging, slow flow, unusual odors, or compatibility issues, please contact us immediately for a free, quick replacement service. replacement filter elements