The STI-6400 Exit Stopper® is a multifunction door alarm that helps alert any unauthorized exits or entries through emergency exit doors. When the protected door is opened, the electronic Exit Stopper® flashes and emits an ear piercing alarm (duration selected by the user). A key operated override will silence the alarm and allow authorized exits. Options include a 15 second delay before arming or tripping, or a 3 second shut off after door closes. Horn volume at 1 ft. is 95 dB low / 105 dB high. This indoor only product is ideal for almost any type of door, mounting or installation, including remote alarm placement.