This fun STEM assembly kit makes an alarm you can install on any door.
This fun science project is a working intruder alarm - opening the door pulls a trigger which completes a circuit, sounding the electronic alarm. The plastic intruder alarm case set comes with cover and base platform and the battery holder has switch and wires already installed. Comes with detailed instructions and all the various parts needed to attach to door and wall. Perfect for those boys and girls wanting to keep siblings out of their room!