Highly effective, alarm alerts you to any unauthorized exits/entries through emergency exit doors and rear doors. Serves as an inexpensive security device and helps stop theft as well.  If the protected doors are opened, the electronic Exit Stopper emits an ear piercing alarm for 30 seconds, three minutes or continuously (as preset by the user). A key operated override will silence the alarm and allow authorized exits. Another option is annunciator mode, in this mode it announces a doors opening with a set of 10 beeps and then resets. Exit Stopper is fitted with a long life 9-VDC alkaline battery. It is available in red or green for almost any type of door, mounting or installation.