Sold as each. New features include an added layer to trap sediment, improved activated carbon filter, and an inner core which water passes over for a cleaner, more refreshing taste. Removes 99.99% of cysts, cryptosporidium, giardia, and total trihalomthanes. Filters up to 100 gallons of water. For SKU # 4194320, 4201042, 4201059, and 4236931. Boxed. Manufacturer's number: RF-9999. Buy Hardware Supplies SKU #: 4194270. Country of origin: United States. Distributed by Pur Drinking Water Sys.