At first we weren't sure if this was going to work. We put both the Booster and the outside antenna in our windowsill (inside), connected the cable to the inside booster, and tried to figure out if we were going to get better cell service by watching the little antennas on our phones. But that proved impossible. The real test came this morning when I went into the kitchen and made a call, and it was strong and dependable. I then walked throughout the house on that call, and it stayed strong. So I can honestly say this thing works. It is also extremely easy to set up. The only tiny negative is that you have to have a place for the inside booster, and you have to hide the wires. But if you need stronger cell service, this works.