A DECT baby monitor sends a digital signal between the baby and parent unit. The sound is clear and the signal is 100% interference-free with most DECT baby monitors. A baby monitor with DECT connection only transmits audio, so you can hear what your baby is doing. To choose the best DECT baby monitor for you, it's important that you consider the extra functions. These include playing lullabies, turning on a light, or monitoring the temperature in the nursery. As a result, you can be sure that you choose a baby monitor that suits your needs. Because of the secure connection, you can't expand a DECT baby monitor with multiple baby units.