High-tech device for detective role-playing games. Hide the transmitter and track it down with the detector. Detector shows the direction and distance of the transmitter via LED scale. For exciting treasure hunts, even in the dark. Solve exciting detective cases with the help of sound! With the "The three ??? Ultrasonic Detector" For example, children from the age of 8 look for a treasure or a suspect who is hiding in the apartment, in the garden or in the classroom. The instructions explain the best way to do this. The kid with the transmitter chooses a hiding spot and the other starts searching. The LED scale on the detector shows little noses whether they are moving in the right direction, for example on a treasure hunt, are getting closer to the hiding place and how they are correcting their route. A little tip: are many LEDs flashing? Then the transmitter can't be far away!