The Waterdrop tankless reverse osmosis system features NSF/ANSI 42, 58 and 372 certifications, 11-stage filtration and alkaline mineralization. It delivers up to 1200 GPD with a 3:1 pure-to-drain ratio. The smart faucet displays TDS and filter life and supports measured dispensing. The mineral filter may slightly increase TDS. Countertop drilling is required. | Waterdrop | | X12-WAQ Under Sink Alkaline Mineral RO Water Filter, Bronze Faucet, EXTRA 2 F2 Filters | Best Buy