Originally Posted by robones

You purchase this relay.

Blinking Smart Stop - Flashing Brake Light

and you install it between the power source and the actual fog light. If you purchase the fog light from Z1 motorports, it includes a great schematic on how to install you fog light for various functions, i.e. reverse, brake, fog, turn whatever you like.

If prefer the brake function because you utilize this safety feature more often than say, using it as a fog light for foggy conditions and/or rain.

This site tells you this type of function is legal because this relay converts your light to a steady one after 4 seconds. I believe that if it remains blinking, it then becomes illegal as only the hazards should be blinking in dangerous conditions.

Happy modding!