Valcom's V-9945A Loud Warble Ringer Horn is a two-tone horn designed to broadcast tones throughout your organization to notification individuals of shift changes, breaks or other important announcements. The V-9945A broadcasts a loud warble as long as an input signal is present and have the ability for night rings for after normal business hours. The V-9945A is a two-tone ringer horn that provides amplified electronic tones for signaling in large, noisy or outside areas.