It is not just playing DVDs and CDs, but also allowing the units to play more video games, such as you can hook up an Xbox or play station, and then you can play more games. This is a useful function for children, because they can be occupied without any sound.
my sis asked me to buy the headrest car dvd for a road trip..but i think portable dvd can entertain people as well..could u name something good abt the headrest dvd?

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