There are several devices to signal commercial or priority vehicles

As directional lights,  they are installed at the front of the vehicle. Encased, they can be mounted on the bumper, on the hood or on the radiator grille. 
Some models may be fitted.

To be used within the lights of origin 
or special blue or orange xenon bulbs 
or visor mounting flash 
Click on the arrow to see the animation.

 The example bellow, shows a vehicle equipped with these two devices.
 
 

At the back end of the vehicle:

called also in French oreilles de Mickey (mickey mouse ears) 

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