Athearn HO 45' Smooth Side Trailer, Metallic Purple Overview
Semi-trailers were invented by August Fruehauf in 1914.
Semi-trailers are designed to transport the most versatile of dry products due to the fully enclosed nature of the trailer, which protects the freight from the elements. Common lengths in North America are 28ft-0in, 40ft-0in, 45ft-0in, 48ft-0in, and 53ft-0in.