4PCS Water Filter Replacement for BERKEY Black Activated Carbon BB9-2 Filters for Gravity-Fed Water Filter System P20250110581 [Filtration precision up to 1 Micrometre]: For excellent filtration performance, this filter uses high-quality coconut shell activated carbon as the filter material, with a filtration precision up to 1 micrometre. Efficiently removes impurities such as sand, rust, sediment, and odor, while effectively reducing residual chlorine with a removal rate of more than 99%. [Compatible Models]: This filter is compatible with gravity-fed water filtration systems including Travel, Grand, Royal, Imperial, and Crown Series. The precision design of the washers and wing nuts ensures a secure connection and helps prevent leakage. No primer required; it can be installed and used after replacement, reducing initial flushing time. No low water flow issues. [Durable Lifespan]: To extend the life of your system and maintain optimal performance, replace the filter every 6,000 gallons (depending on water quality). It is recommended to fully submerge the carbon filter once a week to ensure proper siphoning in the drip system. [Note]: Before installing the filter, soak and rinse the filter to remove any residual manufacturing dust. Color: Black Material: Coconut shell activated carbon Package Contents: 4 water purification filter elements Only the above package content is included; other items are not part of this package. Note: Lighting and display differences may cause slight variations in color between the image and the actual item. Measurement may vary by +/- 1-3 cm.