Watts Premier 560088 Lead, Cyst, VOC Carbon Block Two Stage Replacement Filter Pack Replacement filters with water filtration system can save over 4,500 half liter bottles per filter Reduce environmental impact of filter, certified for 600 gallons Specially formulated carbon block NSF certified for the reduction of lead, cryptosporidium, giardia, and entamoeba Also certified for harmful volatile organic chemicals such as herbicides, pesticides, insecticides, and more Fits all standard under counter and counter top filtration systems