DayZ field wiki · Survive
Road flare
A billboard
Short answer
Bright, rude, a meet or a cry for help. Everyone sees it. That's the point.
Also: flare
How it works
Flares light a circle and write a pin. Use them when you mean to be found.
What to do
Meet, distress, or a bad idea. Levi says which.
Don't
Don't toss one on a stash.