BEST OVERALL: YoLink LoRa Smart Window Door Sensors. ↓ Jump to Review. BEST BANG FOR THE BUCK: GE Personal Security Window and Door Alarm. ↓ Jump to Review. UPGRADE PICK: Ring Alarm 5-Piece ...

When placed against a door on the floor, this nifty security device will blare a loud alarm if someone attempts to open the door. 15.99 6% OFF $ 14.99 at Amazon ...

This article was originally published with the title “ Detonating Door and Window Alarm ” in Scientific American Magazine Vol. 8 No. 8 (November 1852), p. 60 doi:10.1038 ...

The door alarms, which cost about $5 each, are installed on every door that leads outside. If their 4-year-old son, who has autism, decides to run off, the alarms alert them immediately.