Product Description This push button 5 Micron Carbon Pre-filter is designed for the Four Stage RO Pure, Pure Plus and Zero Pure Plus Reverse Osmosis Systems. This Carbon Pre-Filter is made of high quality activated carbon. It reduces chlorine taste and odors, as well as conditions the water before it is treated by the reverse osmosis membrane. From the Manufacturer Product Description Five Micron Pre-Carbon Block Water Filter. Contents: 5 Micron Carbon pre-filter. Made of high quality activated carbon. It reduces chlorine taste and odors, as well as conditions the water before it is treated by the reverse osmosis membrane. Applications: RO-PURE/RO-4 Compatible with the Premier RO-PURE Reverse Osmosis and Filter Pure Filtration System. This Carbon Pre filter is made up of high quality active carbon. Active carbon enhances the flavor and taste of the water.