I had bought two of these to install on the water heater and A/C closet door. I had already replaced all other knobs in the house with lever style knobs. They are such a pleasure to install. The lever is removable so you can install the inside retainer ring. You have clear access to the screws and it all goes together great. But with this knob you have to do some strange twist and push action to attach the inside knob. And hope that it caught the head of the screw correctly. You try to tighten the screws by putting the screw driver in an awkward angle and trying not to knock the trim ring loose again. In this process you booger up the screw head plus you are trying not to mar the finish on the knob. If this had been designed so the knob could have been removed this would all been a snap. Takes too much time and patience to get done.