Easy installation and they work great! Beats the heck out of the other two electric attic fans I have in the middle of the house. My brother easily installed one of these over my garage and another on the other side of the house, it took him less than two hours to do both. To give you an idea of the area of the roof, when i purchased the shingles to have the roof done, I bought 65 squares worth.
I can only imagine how much I would’ve saved (in electrical bills, because the other two I have are electrical) had I discovered these solar fans back in 2009, which is when I had my flat roof lifted to a 6/12 roof pitch. These solar fans are quiet and seem to make a big difference in the temperature of my attic, i decided to buy these myself after getting a quote from a radiant barrier technician, who quoted me $1100 for one.
Easy installation and they work great!