The compact MAGNETIC DOOR ALARM utilizes magnetic attraction to trip the 110 decibel alarm. Bolt the base to the door or window frame and attach the sensor to the door or window. If the door or windows is opened, the alarm is sounded. This solution will work for most any door or window, even a sliding glass door. Three lithium button cell batteries are included.
Review by Bruce M. on Feb 23, 2011
We've had problems with things missing at work. I use this on my custodians' supply closet. What a miracle. We don't seem to have things missing anymore. Works well, highly recommend it.