Ok.  These curtains are amazing at blacking out a room.  That is for sure.  However, they are black on the other side...and that is where the problem is.  These were bought for a room that is east facing so the light is crazy and so is the sun.  Well...I an take the light over the heat.  The heat that radiates off these is absolutely insane.  I could not even handle walking by.  Seems like a huge flawed design.  So if you are not in a spot where you get direct sun...the black out is awesome.  I will keep them because that heat retention might work well in the winter months...but not for the rest of the time.  Happy Shopping