NEW and Improved Carbon Chlorine Replacement Block for Single Stage EZChange Under Counter Filtration System featuring our new upgraded design. The innovative twist-and-lock design makes filter changes faster and easier than ever. Fully enclosed housing protects the carbon filter block inside. Compatible with all EZChange systems. Typical useful life approximately 4 months but more frequent replacement may be required. Filters Chlorine, Taste/Odor, Lead, VOCs, & Particulates AND PFOA/PFOS, Emerging Contaminants, Mercury, Cyst, & Turbidity.