The PulseMINI™ radar can measure a car with a good radar return from about a half a mile away. Some larger cars have more flat surfaces and will remain visible to the PulseMINI™ radar even further away. Some cars have a smaller profile and will have less range. A large truck with a flat metal front will reflect a strong signal and remain visible even more than half a mile away. You may not get a reading if you are too close to a very large moving object.