Wireless 2.4GHZ Transmission: Digital signal transmission, stable and non interference, digital signal encryption transmission, good security. Two Way Intercom: With a built in microphone and speaker, you can talk to your baby from a distance without having to run back. Room Temperature Monitoring: The built in alarm will warn you when your baby's room temperature is above 30 degrees or below 20 degrees, providing excellent monitoring of your baby's room temperature on a daily basis. VoX Power Saving Mode: Set VOX mode (High 50DB, Medium 55DB, Low 60DB), the display will automatically turn on when there is sound in the baby's room and turn off when there is silence for about 30 seconds. Use this mode to save power. Play Lullabies: 8 lullabies are built in to help parents comfort their babies and put them to sleep, so that parents can save their energy and effort.