Barrier hardness replacement filter cartridge for barries water pithers. Three cartridges in one pack means three times more clean water for your home. Designed for effective purification of hard tap water from organic and inorganic impurities. STAGES OF PURIFICATION: 1. Hermetic thread: eliminates the entry of unfiltered water into filtered water. 2. Nano plus technology: increases the sorpion capacity of the active components of the cartidge. 3. Silver impregnated coconut activated carbon. 4.Coconut activated carbon removes chlorine and organochlorine cantaminats. 5. Mixture of ion-exchnge resins reduces water hardness. Cartridge life depending on quality of water source: 2 people 90 days appr., 3 people 60 days appr., 4 peaople 45 days appr.