A low bed semi-trailer is a type of heavy cargo vehicle specially designed for transporting heavy vehicles (such as tractors, large buses, special vehicles, etc.), rail vehicles, mining machinery, forestry machinery, construction machinery (such as excavators, bulldozers, loaders, pavers, freighters, etc.) and other heavy-duty cargo. It is characterized by a low center of gravity, which makes it more capable of transporting high cargo and passing overhead, while also improving stability and safety.

The low-bed semi-trailer (also known as a low-loader) is a specialized heavy-duty transport vehicle designed for carrying oversized, heavy, or tall cargo such as construction machinery, excavators, bulldozers, and industrial equipment. It features a drop-deck design with a very low loading height (typically 0.8 to 1.2 meters from the ground), achieved by a gooseneck front section and a flat lower deck. Built on a multi-axle chassis (2 to 5 axles or more) with high-strength steel construction, it offers load capacities ranging from 20 to 150+ tonnes. Some models include removable goosenecks, hydraulic ramps, or extendable decks for easy loading and unloading of non-roadable equipment.