The huge majority of remote controls use IR (Infrared) technology, which typically means the remote control will have a reasonably short range and must be pointed toward the IR sensor on the device you are trying to control (and it won't work through walls!) However, RF (Radio Frequency) eliminates the limitations of IR, even allowing remote control signals to travel through walls and floors. This device converts virtually any remote control that uses AA or AAA batteries into an RF remote. With this simple setup, you can control your devices from 30 metres away. No line of sight needed!