STOP! That familiar sign that prompts motorists to brake at intersections was the first transportation management item made by Econolite Control Products. The company now manufactures and distributes much more sophisticated traffic control equipment, including loop traffic control systems, vehicle detection systems, traffic control cabinets, and signal display equipment. Econolite boasts about 5,000 arterial systems in operation, controlling 100,000-plus intersections, and more than 90,000 wide-area video vehicle detection systems set at intersections and on freeways. Econolite began in 1933 when company founders developed a stop sign with a built-in flashing red light, controlled by a bi-metal sun valve.