We've owned a hand-held NAT structured water filter for years, and have experienced the results first-hand, as well as introducing their technology to friends and family. It was only a matter of time before we upgraded and installed this one under our sink, and it significantly reduces our structuring time while keeping the water smooth, energized and happy. (yes, water can be happy... Google the recent scientific breakthroughs showing that water has memory!) Not only are we thrilled with the structuring, but NAT was able to ensure we received the product as expected and we experienced immediate and above-and-beyond customer service. What a great company. Our only other concern before buying this was that is might have been a counterfeit seller because of such limited reviews, but in good news this is the legitimate company and the product is 100% authentic. Thanks NAT!