I knew I was sensitive to EMF’s because I could feel it. Not only did I have extreme anxiety, but it felt like my organs were vibrating, and it was very scary. I convinced my husband to purchase the Portable Qi Shield first, because of their great return policy. We have wired WiFi, but we can also turn on wireless. Wireless is what caused the symptoms. When I got the portable unit, I put it in a backpack and wore it for 3 hours around the house while I blasted music over our wireless. I really put it to the test. Normally this would have caused a meltdown of symptoms within a few minutes, but I felt absolutely nothing! I danced all over the house with joy, because I knew this was the answer. Even though we were wired, we picked up symptoms from the neighbors wireless WiFi. I’ve had the Qi Home unit for just over a year now, and I’ve never once experienced those awful symptoms since we set it up. I’m home a lot, but I’ve noticed that I now have greater resilience to WiFi when I leave the house. I LOVE my Qi Home and will never be without it! If you are not sensitive to EMF’s, you probably won’t feel a difference, but it’s making a difference anyway! My husband doesn’t notice anything himself, but he sure notices a difference in me! I can’t recommend this enough!