The Little Luxury 6-Stage RO Replacement Filter Cartridges provides exceptional water filtration in a cost-effective bundle. The replacement filter cartridges are easy to replace and maintain. Advanced 6-Stage Filtration Process: Stage 1 - The Pre-filter Sediment Cartridge: Removes larger suspended particles, filtering sand, rust, mud, and sediment in water. Stage 2 - Taste/ Odour Granular Activated Carbon Cartridge: Reduces unnatural tastes and odours and filters organic sediment, as well as other contaminants and impurities in water. Stage 3 - Post-filter Activated Carbon Block Cartridge: Reduces chlorine, organic chemicals, unnatural tastes and odours, cloudiness and other chemicals found in tap water. Stage 4 - RO Membrane (0.0001 micron): Removes smaller suspended particles, bacteria, and hundreds of impurities which are reduced by over 99% through the 0.0001-micron TFC Membrane layer. Including fluoride, calcium, magnesium, organic materials, and other harmful minerals, including other soluble salts found in tap water. Stage 5 - Inline Post Active Coconut Carbon Filter Cartridge: Restores essential minerals and improves water quality by removing unnatural tastes and odours. Stage 6 - Post-mineral Filter Cartridge: To enrich water with healthy essential minerals including Calcium, Magnesium, Potassium, Sodium and other readily found minerals in many natural mineral waters.