These things are especially useful when there are no power outlets near the intercom for the necessary power supply units. Fully charged once in the intercom they provide the intercom on nights away (z. B. for monitoring and communication between foster child and caregiver) with energy and should this after several hours use (can not say how many hours of standby are possible) be empty How to do from the convenience store. A full charge takes about 4 hours. The batteries fit to the millimeter in the intercom and need no longer be taken out for charging. This works just like charging a mobile phone. My full recommendation in the absence of an outlet in Rich width of the installation location of the intercom.
