Signal Dynamics Tri-Star Control Module Converts your rear turn signal lights to function as additionalbrake lights When the brakes are applied, the turn signal lights illuminategiving your more rear visibility when you are stopped If a turn signal is applied, it has priority over the brake light function on the side that is selected. If the turn signal is canceled and the brakes are still applied, the brake light functions of the turn signal lights illuminate steady on The included Dual-Load Equalizer is designed to fix the problem when you have changed your stock turn signals to L.E.D.s and they flash quickly or not at all