Culligan Replacement Cartridge for IC and US-Series, Level 4 -Premium Filtration: * Easy-Change replacement filter for US-EZ-4 * Level 4- Premium Filtration * Removes bad taste and odor, aesthetic chlorine taste and odor * Removes sediment, lead, cysts such as giardia and cryptosporidium, mercury, turbidity, Particulate Class I, VOCs, MTBE and chloramines * Twist-on, twist-off mechanism * Quick-connect fittings * Cartridge life: 500 gallons * Includes manufacturer"s 2-year limited warranty * Model# RC-EZ-4