Build a door alarm for your bedroom and stop unwanted intruders! The Spy Science Intruder Alarm Kit contains a snap together circuit that’s easy to construct and mount.

Trespassers dislodge the trigger plate by opening the door, which completes the circuit and activates the alarm! The kit includes: 1 x electric blue alarm case, battery holder with switch, buzzer, metal pegs, trigger plate, wall mount, trigger plate holder, string, adhesive tape, cardboard door hanger and full colour instructions. 2 x AA batteries are required (not included). Colour of alarm shell may vary.