NU Aqua Efficiency Series Tankless 600GPD Reverse Osmosis System 2:1 Pure To WasteWith the compact Nu Aqua 600GPD Tankless Reverse Osmosis System, you get four stages of premium water purification at 25% of the size and hundreds of times faster than other RO filters. Let's face it, most RO systems take up lots of space under your sink, and those that don't take up lots of space usually don't filter more than large particles. With this tankless RO system you get all the delicious, safe water you want at a fraction of the time and