SensAlert has capacitive sensors that are activated by electrical conduction, allowing it to automatically recognize when a child is seated in a car seat (since the human body is an excellent conductor of electricity). This feature distinguishes SensAlert from basic pressure sensors, which get activated by placing any item on them. However, it's important to note that other electrical conductors (for example metal and items containing liquids), can also trigger the capacitive sensors. Therefore, it's crucial to avoid placing conductive materials on top of SensAlert. To prevent unnecessary alarms, please ensure that the SensAlert is free from any conductive materials, once you and your child exit the car. If you require further assistance or information, please don't hesitate to contact our support team.