The only types of third brake lights you can legally use on the road need to be red and need to illuminate a steady-burning red light the moment you apply the brakes and until you stop braking. The light needs to be on and working in conjunction with the other two brake lights on your vehicle.
Whether it be a thin strip of light just under your roof or a large red circle within your 3rd spare wheel, you can choose between a wide variety of third brake light designs, all of which do what they are legally obliged to do while also looking cooler than those you get on a standard Ford Bronco Sport.
Besides needing to be red and steady burning, a third brake light needs to be bright enough to be noticed by the drivers around you. This means that the light needs to be more powerful than your taillights, but not overly so to dazzle everyone around you.
As third brake lights need to be bright and always visible, you should go for LED third brake lights and avoid going for halogen lights as those can sometimes be difficult to spot when illuminating near more powerful LEDs.
Make sure to mount your third brake light somewhere near the center of the car’s rear which means that you shouldn’t put it left, right, or anywhere else where it can be blocked or difficult to see. Also, follow all the instructions if you want to install it yourself or pass the job to an experienced mechanic.