W. Va. Code § 17C-1-17: Pole trailer.

"Pole trailer" means every vehicle without motive power designed to be drawn by another vehicle and attached to the towing vehicle by means of a reach, or pole, or by being boomed or otherwise secured to the towing vehicle, and ordinarily used for transporting long or irregularly shaped loads such as poles, pipes, trusses, or structural members capable, generally, of sustaining themselves as beams between the supporting connections.