The unit I received contained no instructions; no problem go online to company site to get them.  Easy to install put the unit near window or anywhere you have service (at least one bar) then put the antenna at least ten feet away.  The antenna cable is only 20' so it is difficult to go further than that unless you are going to have cable in front of you, then the next problem is that you can not have the cell phone near the unit so in my 15' x 12' office I could not move the unit and antenna around so that I could get a green light as you also have to have phone within 6' of antenna.  Gave up after an hour of moving all over only to get a green light for a few moments then back to red.  Did nothing to improve signal since I could not get a green light, presumably this would have indicated that I have a signal that my cell phone then would pickup.  I may try the other four person Sprint device the company has?