I ordered this to replace an old one that was a pain to use, the switches were on the side and not accessible. This unit has all front accessible buttons and battery door. I highlighted some functions, with a sharpie, to make it easier for me to identify. Our thermostat is located in a dark corner of our home. This was easy to install, I used the included wire identification stickers, so I didn't mix up any wires. In less than 10 minutes it was installed. You will need a small Phillips screwdrivSee full review