About This Please note: The filter indicator requires batteries, which are sold separately. Compatible Models: This RF-20 Sediment, Pre-Carbon Plus, Post Carbon Block Replacement Filter is designed to fit your Brondell Circle RC100 Under-Sink Reverse Osmosis Filtration Systems, ensuring a secure fit for reliable use. Multi-Layer Protection: The sediment filter captures rust, sand and large particles; the carbon block pre-filter reduces VOCs, chlorine and soluble impurities; the carbon post-filter removes residual VOCs, impurities and chlorine taste and odor, providing clean and fresh water. Easy to Install: It only takes a twist to replace the filter for the Brondell Circle RC100 Under-Sink Reverse Osmosis Filtration Systems in three seconds with no tools required. Extended Filter Longevity: Replacing the filter takes minutes and requires no special tools. Depending on water quality, it offers 6-9 months of consistent filtration, cutting down on frequent replacement trouble. Overview Material : Sediment, Pre-Carbon Plus, Post Carbon Block Filter Product Dimensions : 3"D x 3"W x 11.5"H Item Weight : 3.3 Pounds External Testing Certification : NSF Product Benefits : Effectively reduces various contaminants and improves water taste.