Built-in 4 lullabies may help the parent comfort the baby fall into asleep; Built-in Mic, Two way audio between the camera and monitor, you can talk back to baby. Keep an eye on your baby room temperature all day long and all night long with automatic IR night vision(indoor effective range 5m/16feet) without worries. Standby/Power Saving Mode: In Standby mode(Except No power), Camera/Sound seems to be turned off(saving battery), it will activate when there is movement or noise. It will usually go into the screen monitoring by just press the Home/OK button Within 10m transmission range indoor use, dynamically select clean channels to advoid interference from other 2.4GHz device.China