Enjoy peace of mind with the Philips AVENT audio baby Monitor SCD502/10. Dect (digital enhanced cordless telecommunications) technology guarantees Zero interference from any other transmitting product like other baby monitors, cordless phones and cell phones. It also provides high quality, crystal clear sound so you can hear your baby anytime. The five sound-activated LED lights alert you of the noise level in your baby's room even when the parent unit is muted. If your baby is restless when you put him or her to bed, You can help soothe and calm your baby to sleep with the warm tranquil glow of the night light. With an indoor range of 150 feet and an outdoor range up to 1, 000 feet, you can be fully mobile in and around the home. Parent unit alerts you when your monitor is out of range or when the power is low, so you always know when your monitor is in range and connected.​ The parent unit can be outlet or battery powered using AA batteries (not included). with batteries, The parent unit offers the freedom of cordless use for up to 24 hours before recharging is required (depending upon battery type and use)​. a unique smart Eco mode automatically minimizes transmission power and increases battery Lifetime. The closer the parent unit is to the baby unit, the less power is needed.​