2-wire power supply unit required to power the external unit (terminals L1 - L1) and the support column (terminals L2 - L2). Equipped with 1 terminal for line termination art 1216. Input voltage 110-240Vac. Compatible with audio/video unit art. 4681 and 1621VC and audio unit art. 1621. Dimensions: 106x89x62mm (6 DIN modules).