Height pole (high-pole car)

A lead pilot car fitted with an adjustable pole set to the load height to catch low obstructions.

A height pole is a flexible, non-conductive pole mounted on a lead pilot car and set slightly above the load's height. As the car drives the route ahead of the truck, the pole strikes any bridge, sign, wire, or overhang that is too low — giving the driver warning to stop before the load hits it. A car equipped this way is called a high-pole car, and most states require one once a load exceeds a set height (commonly 14'6" to 16').