[box type="shadow"]Underglow lights are neon lights attached to the undercarriage of a car, motorcycle or truck. These lights provide a colored glow under the vehicle and make it appear as if the vehicle is floating. Adding underglow lights is a popular feature on customized cars. Underglow lights are sold in red, green, blue, yellow and purple and are can be either neon or LED in nature. Some states, such as Oklahoma, have explicitly outlawed the use of underglow lights while other states, such as California, simply place limits on them. There is no federal law on the use of underglow lights.[/box]
[box type="shadow"]Red and Blue Lights are Problematic
Red and blue lights are prohibited in many states as these colors are often reserved for police and ambulance vehicles. For example, in North Carolina it is unlawful to have aftermarket red or blue lights installed on a vehicle. The policy behind this relates to confusion with public and government services. A driver may see red or blue lights coming up behind him and pull over thinking it is an emergency vehicle or a police officer, thereby causing an unexpected collision or other traffic incident.
Limits on Placement and Candela
The amount of light put out by underglow lights may also be limited by state law. For example, in California underglow lights can not emit more than 0.05 candela per square inch. States may also limit what sides of the car can contain underglow lights. For instance, underglow lights might be permitted on the right and left side of the car but not in the front or rear of the car.
De Facto Bans
Some states, such as Connecticut, require all aftermarket lights be shatterproof. Connecticut does not expressively prohibit underglow lights by law but since no underglow lights on the market are shatterproof, they are thereby unable to be on the market. Other states, such as Nebraska, require the lights not be visible under the car, making it difficult to add lights to the car without doing substantial work to the body.[/box]