Philips Avent was the first to sell 2 way digital baby monitors using DECT technology in the U.S. The SCD510 digital baby monitor uses DECT to provide a secure connection between the parent and child monitor units that is guaranteed to be interference-free. You can adjust the sensitivity of the microphone, and the monitor automatically scans 120 channels to make sure there’s never a disruption (aside from any that your baby may make). There’s a talk-back feature, too, so you can talk to your baby from another room. You can plug it in or roam up to about 1000 ft with the rechargeable batteries. I like the long battery life on this baby