The Telelink connects the Digisystem DC20 to a landline telephone. The telephone handset is connected to a small switch box with a cable going from the switch box to the telephone handset socket on the telephone base. This allows other people, who do not require hearing loss assistance, to use the phone normally. Another cable is connected to the Telelink. This allows the user to communicate with the caller using their DC20 Conference Microphone and hear their reply with any of the Digisystem Receivers. They don't listen or speak using the handset. The DC20 also has a menu option to include another Digisystem microphone, for example the DM05, to be used as a remote microphone allowing the user to be hands-free and move freely whilst speaking. There is a push button switch, on the Telelink base, that allows the user to switch between listening to people around them, and then press again to only hear the caller on the phone. The Digisystem Telelink is mains powered. The unit comes with a selection of three cables, to choose one, which is dependant on the handset wiring.