I purchased one of these shades (23") for our back porch door, to replace a set of mini-blinds that our landlord originally installed.  First off, this looks a heck of a lot better than the mini-blinds!  That said, the installation was actually a bit trickier than I expected (I am a pretty handy dame, AND I even watched the YouTube video on the subject).  I'm very glad that I finally got them to work, but I also have to say that my blind wouldn't stay down at first AT ALL-- if this happens to you, I found jostling/pressing on the thicker end of the roll housing (where the spring mechanism is) finally made the blind stick in place.  Really pretty in a clean lines type of way, but a bit too fussy for my taste.