These speaker units have been developed specifi cally for use in emergency and evacuation systems (VES) and each has its own ceramic terminal strip and thermal fuse. These ensure the protection of the line connecting the loudspeakers if a fire puts one or more of the speaker units connected to it out of use. This speaker units are fitied with fi reproof cable according to UNI 9795 2010 (length 80 cm). These columns can be turned in any direction thanks to the S4-B swivel joint included in the supply.