Trolleys of different uses have different body Structures. General-purpose four-wheeled trolleys have a cargo platform for the most part. The special trolley is a large structure, some car system into a box-shaped, suitable for handling light weight and easy to unload items; some of the body extends brackets to facilitate the placement of rods, shafts and pipes and other parts; some of the body shape is completely in line with the goods, such as gas cylinder car; some are small enough to be folded and portable; Paper rolls and other tubular goods, the car body has two flat steel formed a low inclined plane, in order to facilitate the barrel-like roll on the roll, such as barrel cargo loading and unloading vehicles. Modern trolleys are fitted with rolling bearings, wheels with solid tires or inflatable tires.