This thing works great! Smoke use to pour into the room, not any more!! I had to modify it as the spring part really didn't work.
The smoke guard has worked as advertised. It was relatively easy to install however, my fireplace opening was exactly the maximum width specified, and the spring tension wasn't enough to hold the unit in place while the caulking set
I had to prop the unit up to hold it in place. I would only recommend this for fireplaces that are 4 to 6 narrower than the specified maximum. Otherwise, I am very happy with the product.