The Brondell H2O Cypress Carbon Block filter (HF-33) is the final stage in the advanced Cypress filtration system. The Carbon Block filter further reduces particulates, bad tastes and odors, and water contaminants such as chlorine and harmful volatile organic compounds (VOCs), improving the taste of the dispensed water. The HF-33 filter significantly reduces harmful chemicals like Atrazine; Chlorobenzene; Trihalomethanes; Methoxychlor; Endrin; 2,4-D; Benzine; DBCP and 98% of Aesthetic Chlorine from your tap water for a healthier home and family. Choose Brondell H2O for better water.