STI’s newly redesigned exit stopper door alarm flashes while it emits an audible alarm — helping to further attract attention and deter wrongful use of a protected door. The exit stopper (STI-6400) is easy to install and the stop sign shape is another way it helps deter misuse. When activated, it sounds a warning alarm and now includes a flashing LED. A key operated override will silence the alarm and allow authorized exits. Another option is annunciator mode. In this mode the alarm will beep several times and reset when the door is closed. The self-contained alarm includes symbols and 21 labels to warn in a second language. Alarm sounds when turning on or off, includes a low battery warning, extended battery life mode (battery included) and a dry contact Form C relay option. For indoor use only.