CWR-DC3UC Crown Double Under Counter Imperial Ceramic VOC/THM Filter Crown Double Undercounter Imperial Ceramic VOC/THM Filter a ceramic filter cartridge and a VOC/THM cartridge. Volatile Organic Chemicals VOCs from industrial sources or chlorination by-products are adsorbed more effectively by coconut based activated carbon media. The filter is rated for chlorine reduction at 90% at 1ppm and VOC reduction 95% at 1ppm for up to 500 gallons. The second filter removes volatile organic chemicals and THM or trihalomethane. According to the Collins English dictionary Trihalomethane Chemistry a type of chemical compound in which three of the hydrogen atoms in a methane molecule have been replaced by halogen atoms, esp by chlorine in drinking water. Trihalomethanes are thought to be carcinogenic. PLUMBING AND INSTALLATION IS REQUIRED FOR UNDER COUNTER MODELS Replacement filters for this unit is the RF-IMPUC RF-CB5 The CWR-DC3UC primary water filter has a three-stage filtration system First Stage a Bentonite Kieselguhr ceramic that filters out parasites, bacteria, rust, dirt and sediment from the water. A small amount of silver baked into the ceramic inhibits the growth of bacteria. Second Stage activated coconut shell carbon which reduces chlorine, chemicals, pesticides, bad taste and odors. Third Stage heavy metal removing compound, which is incorporated in the carbon block called A.T.S. titanium zeolite that reduces lead and copper. Specifications The housing is made of medical grade-ABS plastic. The flow rate of the ceramic filter is 1.5 gpm gallons per minute at 45 psi and the filter is effective up to 1,200 gallons. Tested to Remove Contaminants Such as Cysts parasites ... 99.99% Turbidity... 99.96% Lead 150ppb... 98.25% Bad Taste Odor...Class I Particulates...Class I Chlorine... 98.25% This item ships from a separate warehouse and may require extra time for delivery.