the system can connect to the internal communications between the apartment or the floors together?Can expand the screen door bell in the apartments? in this case the model sht-7017xmimages are stored for review? the storage duration for how long?video images are only observed directly or be stored for review? maximum storage time for how long?can you explain to me the principle of the operation of camera surveillance
đang được dịch, vui lòng đợi..
