Changing tables are required in installations with more than one access. Its function is to connect the telephone or monitor of the house with the plate from where the call is being made. Maximum 7 accesses. 1 changing table is required for each door entry / video door entry access. Only in case of 2 accesses 1 changer is needed. There are two models that depend on the type of additional access: doorman or video door entry. DIN-10 rail format to facilitate installation inside an electrical equipment box, or they can be screwed directly onto the wall.