If you are looking for a lower cost alternative to a perfect match replacement headrest monitor system, the the Accelevision ZHDB is for your. This DVD headrest monitor system is designed in such a way that the units can display the same source as well as there own internal dvd player. This way your children can do the same thing or when they want to they can do something individual. Enjoy digital media such as MP3 or video files with the USB port and SD card slot. There is no better headrest monitor system than this for the price.