Alexapure 2387 Pro Filter Replacement &ndash; 1 Filter Pack, Black Designed for Use with the Alexapure Pro Water Filtration System Removes up to 99.9999% of all heavy metals, pesticides, volatile and semi-volatile compounds, cysts and bacteria Filter Capacity of up to 5,000 Gallons Use up to 4 Filters for Increased Flow Rate Ready Right Out of the Box  No Priming Necessary