(Package Of 3) KX Matrikx +CTO/2 32-250-125-975 Carbon Block Water Filter (9-3/4" x 2-7/8") NSF Coconut shell Activated Carbon Imported KX MATRIKX CTO Carbon Block Filter Cartridge Efficient Sediment Filter - 5 Micron Nominal Rating Ideal for use in water many purification systems including reverse osmosis (RO) High adsorption capacity and efficiency - 6,000 gallons 3 Pack for additional savings and convenience