This 4-pack of activated carbon water filters provides a cost-effective solution for maintaining clean, great-tasting water. Designed as direct replacements for BB9-2 filters, they are compatible with Berkey Travel, Grand, Royal, Imperial, and Crown series gravity filtration systems. Key Features: • High-Quality Filtration: Utilizes premium coconut shell activated carbon to filter down to 1 micrometre, effectively removing sand, rust, sediment, and odors. • Reduces Chlorine: Effectively reduces chlorine with a removal rate of over 99%. • Easy Installation: Precision-designed washers and wing nuts ensure a secure, leak-proof fit. No primer is required; simply install with minimal pre-flushing. • Durable & Long-Lasting: For optimal performance, replace the filter every 6,000 gallons (depending on water quality). In drip systems, fully submerge the carbon filter at least once weekly to maintain proper siphoning. • Ready to Use: Includes 4 black water purification filter elements. Note: Before first use, soak and rinse the filter thoroughly to remove any residual manufacturing particles. Specifications: • Color: Black • Material: Coconut shell activated carbon • Package Contents: 4 x Water purification filter elements Please note: Slight color variations may occur due to light reflection or display differences. Measurements may vary by +/- 1-3 cm.