Our department has flashlights that have both LEDs and xenon bulbs. I turn on just the LEDs and shine them behind me when walking to the car I’ve stopped.
The LEDs are just bright enough to be visible to cars approaching from the rear, but aren’t visible to the offender’s car because of all of my cruiser lights facing them.
Regardless of the time of day, I always turn on my rear facing radar when conducting a traffic stop to alert me to vehicles approaching from behind. It’s come in handy quite a few times when stopped near a turn.