The SCD502 is a baby monitor from Philips Avent using DECT (digital enhanced cordless telecommunications) technology. This makes the baby guard uninterrupted, so it does not take up interference from, for example, other baby guards and mobile phones. With data encryption, you get a secure and private connection so that you are the only person to hear your child. The parent unit has lamps that show the noise level inside your child. It also shows when your baby monitor is out of range or when the battery is weak. It has a range of 300 meters outdoors. The baby monitor has a battery life of up to 24 hours. It also has a smart Eco mode that automatically reduces the power required. It draws less power the closer the units are to each other. Frequency band: DECT. Number of channels: 120. Volume control: Yes.