It is possible to replace the existing screen with the Class 100X - Villa or single-family house, duplex: replacement without modifying the video door entry system wiring - Complex or apartment building: depending on the characteristics of your installation, replacing the apartment screen may be sufficient or it may be necessary to add an additional special power supply ref. 346020 Regarding the sizing of video door entry systems for apartment buildings, refer to the General Installation Rules of the 2-Wire System Technical Guide