Well with a large window like the back window they do it a half at a time. they'll cut it in half and apply it in sections. Sometimes companies don't offer a "warranty" on the back window because it's 10x harder to do it that way. Which is why I'm glad I found pro tint. 4 windows, and the back window...all with a lifetime guarantee. :wink:MadBrad said:They just apply the film as with any other window. There is no special method for a window with defog elements.