This is as effective as putting magnets on your fuel lines. It does nothing. I got one free with an accessory pack, the case and charger worked. Anyway, I tried the thing with three phones and it made zero difference. Not a single tiny difference. But I am an electrical and electronic engineer with 25 years experience, I make wireless internet gear for a living and I'm an Extra class amateur radio operator, so I knew it not only wouldn't but couldn't work. Basically you can't stick something inside the case of a phone and expect it to improve the signal for an antenna it has no attachment to. In many phones, like the Motorola v60i and Krazr I tried, this thing is inserted between the metal back cover and the metal chassis of the phone, there is no way it can do anything to the signal.Laugh and move on. Keep your money. In Europe the vendors would have been fined tens of thousands of dollars for selling these things.