To confidently and continuously enjoy, cleaner, better tasting mineral water, remember to change your PUR PLUS Faucet Mount Water Filter (RF9999) every 3 months or after 100 gallons of use. As the #1 brand in faucet filtration***, the PUR PLUS Faucet Mount Replacement Water Filter reduces 10x more chemical & physical substances compared to Brita's leading pitcher filter* through its powerful 3-in-1 genuine PUR filtration technology using natural minerals. It has also been rigorously tested and certified by WQA and NSF as the only filter to reduce 70 chemical & physical substances, including lead, microplastics, chlorine and mercury.** Be cautious of 'off-brand' water filters. They are not tested nor certified to filter the same as Genuine PUR PLUS Faucet Mount Water Filters in PUR and Beautiful by PUR systems. Genuine PUR PLUS water filters are the only water filters certified to reduce chemical & physical substances when used with your PUR PLUS or Beautiful by PUR Faucet Mount System. At PUR, we believe that everyone deserves cleaner, better-tasting drinking water. That's why we've been developing innovative, superior water filtration technologies for over 35 years. Disclaimers: *Versus best-selling Brita® pitcher filter OB03. Brita® is a trademark of Brita LP. ** Like other leading brands, PUR does not filter microbes. As of 7/1/23 Brita® and ZeroWater® were not certified to filter microbes. Brita® is a trademark of Brita LP. ZeroWater® is a trademark of Zero Technologies, LLC. ***Based on Nielsen sales data for the 52 weeks ending 7/1/23.