We had some dead spots of signal at my dad's office.  It was not a thing of a single carrier because all were equally affected, and they just kept saying "Sorry we can't take responsibility".  So I investigated a little and found this kind products.  Then made a further investigation in order to decide which model to buy.  At the end I chose this one and I'm very glad I did.  It includes absolutely all that we needed in order to install it.  Its positioning will need a little trial and error but we finally found a sweet spot and so far we have solved all of our problems.  100% recommended.