Model 350WBX Vibratone® horn produces sound by electro-mechanical vibration of a diaphragm. The horn mechanism with diaphragm is attached to the grille. The water- and dust-tight back box is ideal for indoor or outdoor use.Model 350WBX features a die-cast zinc housing with a corrosion resistant polyurethane finish. The rugged outer grille resists vandalism without reducing sound output. The 350WBX is fused and utilizes a terminal block connection.Vibratone horns are excellent for general alarm, start/dismissal, coded paging and process control signaling in areas where their sound output exceeds ambient noise levels. Compact size and a variety of installation options make them ideal for institutional use.