All along the motorway these things are mounted on the crash barrier between the lanes. There's one crash barrier for each direction of traffic and only one of them has these things mounted.
There's a couple of different colors, the darker ones fewer, no idea if that is on purpose or coincidence. There's some with white and red stripes at regular intervals.
I can't figure the purpose of these, does anyone know?
Doesn't take a pro to do that, just a screwdriver, 25 or so feet of flat ground, and some common sense.
It's the common sense that seems to be missing most of the time.