His original idea was quite simple in concept. He wanted to create an illuminated road marker containing its own power source, a solar cell. At night or in bad weather, light from approaching vehicles would generate enough power to light up the marker, which consisted of light-emitting diodes. An illuminated marker would be more visible than a plain reflector, and the idea was that a car passing over the markers would cause them to stay illuminated long enough so that they would provide a warning trail of lights for any vehicles close behind.

He not only overcame the limitations of solar cells, but also managed to engineer markers that turned red to warn when the gap between two cars was dangerously small.

Other features followed. Optical systems inside the casing are able to monitor the atmosphere for fog. Electrical resistance detectors can check for standing water. The addition of a thermometer allows the marker to predict ice.