I confess to being skeptical ahead of time (so many of these types of products don't work) BUT this product really does work.  Generally I pick up an extra 'two bars' of signal reception in weak areas.  In one location, where the phonehad  just dropped out and reported no signal, I was able to get two bars with 3G.  This unit is for a car but I also tried it out at my cabin that has virtually no AT&T coverage (occasionally a text message sneaks through but you can't even send a text).  As I was testing it a call came in that I was able to answer and then I did an internet search.  I've already ordered a larger unit for the cabin.