Looks like a simply elegant solution to a problem.
I have seen people make their own out of PVC.
You should see my poor ol’ license plate after missing many times
Cops don’t much like it but it’s still legal
Up here in snow country the stores sell brightly colored markers to stick in the ground to mark the sides of driveways for snowplows. Two of those and two magnets from Home Depot and you have the same thing…for about $3.