The 801247 was the perfect solution for us.  It was installed in a 100' x 40', metal roofed building with the antenna mounted above the roof. Before it was installed cell phone reception in the building was very poor (and phone battery life was drastically reduced) unless you were near an outside wall.  Now reception is great anywhere within the building.  We had considered the next model up from this one (the 841262) - but because we had a very strong signal outside the building decided to go with this one and we are happy with our choice.