I found this product to be frustrating. I expected instructions on the necessary preparation and how to install the film. None were provided. I contacted the Chat Option on the Wayfair website and they directed me to another site which had instructions. Prep is easy, just clean the glass and then spray with water. Since I was installing this on 3 small windows in my front door I did expect to have to cut it to fit. There is a protective film on the product which is not evident. Trying to peel it off was very difficult. Once you got it started, it came right off. The protection product is much heavier than the film going onto the window. I finally got it up, squeezed out the water bubbles, but there are some still reappearing. I'll have to wait and see if it says stuck to the window. Otherwise it does block out the light as I wanted -see my pictures.

Got this to put in a bathroom window. I like it.

Once I figured out how to install them they were fine. But, they really should include instructions. There is acetate film that need to be removed and it helps if the window is clean and damp.