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 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 prevents leakage. No primer required; it can be installed and used after replacement, reducing initial flushing time. [Durable Lifespan]: To extend the life of your system and maintain optimal performance, replace the filter every 6,000 gallons (depending on water quality). Fully submerge the carbon filter in water once a week to ensure proper siphoning in drip systems. [Note]: Before installing the filter, soak and flush the filter thoroughly to remove residual manufacturing dust. Color: Black Material: Coconut shell activated carbon Package Contents: 4 Water Purification Filter Elements Note: Light reflection and different displays may cause the color of the item in the picture to appear slightly different from the actual product. Measurement may vary by +/- 1-3 cm.