4m kidzlabs spy science intruder alarmLearn the basics of electric circuits by constructing your own working door buzzer. This hands on kit guides kids through the science of connectivity while offering a fun and practical project. Once built, place the buzzer behind your door and challenge friends and family with your cool creation. It's a great way to explore STEM concepts through play. For Ages 8yrs+ Package Dimensions (cm): H: 22 W: 17 L: 6