Electric flat cars, also known as electric flatbed trucks, electric level cars, trolleys, cross-traverse vehicles, electric track vehicles, and ground-crawling vehicles, are a type of on-site rail-based electric transportation vehicle. Firstly, they are rail-type transport vehicles that require the laying of tracks on the ground, typically with I-beam surface contact tracks. Secondly, they are electrically driven vehicles that operate automatically under the power of electric motors and reducers. Additionally, they are flatbed vehicles with a level surface and no box cover, though they can be non-planar in special cases without a box cover. The vehicle body lacks a steering wheel, operating only in forward and reverse directions (even when turning, it relies on the track for maneuvering). This type of vehicle boasts simple structure, ease of use, high load capacity, resistance to dirt and damage, ease of maintenance, and a long service life. Due to its convenience, robustness, affordability, practicality, and ease of cleaning, it has become a transportation tool for frequent, short-distance, point-to-point heavy cargo transport within and between factory buildings.

Electric trolleys are primarily used in mobile lifting water transport vehicles, as well as in electric kiln loading and unloading vehicles for brickworks, kiln factories, refractory factories, ceramic factories, and calcining factories. They are also employed in engineering, tunnels, and environmental sanitation for electric transport vehicles, electric dump trucks, and electric sanitation collection vehicles. Electric transport and dump trucks are further utilized in flour mills, mining plants, foundries, chemical factories, furnace material factories, and farms.