About This Perfect Compatibility: Black block filter compatible with berkey water filter replacement, fits Big, Light, Travel, Go, Royal, Imperial and Crown series water filter systems Upgraded Filtration System: Black block replacement filter was made of high-grade coconut-activated carbon and upgrade hollow fiber membrane ultrafiltration. Hollow fiber pore sizes only 0.01 micron micropores only allow water molecules, beneficial minerals and trace elements in water to pass through, more effectively reducing chlorine, sediment, rust, VOCs, and other contaminants More Efficient: White fluoride filters made of BPA-Free materials and defluorination resin, more effective to absorb Fluoride and Arsenic, longer using time. Activated carbon is added at the end of the filter to improve the taste of the water Easy to Install: No need any tools to install the water filter in minutes. Pls soak and wash the water filter before install and discard the first batch of water after install 365 Day Warranty: Our replacement filter kit for berkey filters and fluoride filters offer 60 days warranty, if you have any dissatisfaction with the product, pls please contact us immediately. We will solve your problem within 12 hours Overview Material : Carbon Fiber Product Dimensions : 10.24'D x 5.91'W x 5.71'H Item Weight : 2.8 Pounds External Testing Certification : NSF Product Benefits : Removes Odor, NSF 53