So I went the rounds on other products before I settled on this simple solution that ultimately was the only one that met our need. The goal was to keep our 3 year old in our house. We were able to use doorknob covers for 2 of our external doors, but our patio door has a handle-type opener and couldn't accommodate a knob cover. The door also couldn't be converted to a knob due to the custom opener / deadbolt system that was installed.Our problem was that the door is slightly offset from the wall and other products proved to be too bulky to allow the door to function after installation. I briefly gave up on finding a solution, but my son later escaped and had to be chased by my wife for several blocks before she was able to catch him. (The boy gives new meaning to the term "stinker") I went back to the drawing board and found this product. I was pretty skeptical, as all of the other products that I had tried were far more complex and much more expensive.I was very pleased to find that the product worked great and installation was a 2 minute process. Now my son is safely contained to terrorize my wife in the comfort of our home and we no longer have to worry about him carrying committing acts of terrorism to the neighborhood at large. It has been several months and he hasn't gotten out yet. (well in all honesty, he did get out once, but that involved a perfect storm of chairs and broom handles and luck, and tiny devious ninja skills. We confiscated the ninja tools (broom handle) and he was back to being foiled. House, thy name is Alcatraz.Thank you for making a product that is as simple as it is effective.