Excellent product although i ordered way too much.    I used on a large bay window and did not measure so i ordered 6 rolls , i only needed 4.    Make sure your window is clean ,  and load a spray bottle with soapy water.  Stuff goes up really easy and looks fantastic from inside and out.  Natural light still comes through , just much softer  .  Be sure to measure once, measure twice and before cutting, measure again .   Took about 45 mins from start to finish to do a very large window.