Excerpts from the book "How Design Changed America" by Henry Keck
Safety at roadside construction sites has always been important, but the lights to warn of unexpected roadside hazards have long had serious defects. In the early 1960s low battery life, theft and inferior lens design diminished the effectiveness of these lights. Most of these products were housed in unattractive metal boxes.
In 1962 Electronic Engineering Company, a California corporation came to us with the need to house their ingenious circuit design which extended battery life. By flashing the light only one tenth of a second per second they achieved a significant breakthrough in battery life. Additionally they had designed a light sensor that would automatically turn the light on at dusk and turn it off in the morning.
50 years later the light is still being produced and is almost ubiquitous on American roadways. It is always amazing to me how an unembellished design still looks modern after half a century of use.