Model TLSP-PB-WS is vandal resistant, two-way talk/listen remote call station with a built-in microphone, 3" speaker and call button, all mounted to an 11 gauge stainless steel faceplate. It comes with a backbox for surface mounting to a wall or ceiling. The call button when pressed activates a Louroe sound activated alarming base station such as the ALA Series and the DG Series. This unit is designed for correctional facilities.