"Trailer" includes every vehicle without motive power designed for being drawn by or used in conjunction with a motor vehicle constructed so that no appreciable part of its weight rests upon or is carried by such motor vehicle, but does not include a municipal transit vehicle, or any portion thereof. "Trailer" does not include a cargo extension.
RCW 46.04.620
Intent-Effective date- 2016 c 22: See notes following RCW 46.04.094.