Electric flat cars, also known as electric flatbed trucks, electric level cars, trolleys, cross-traversing vehicles, electric track vehicles, and ground-crawlers, are a type of轨内电动厂内运输车辆. Primarily, they are track-type transport vehicles that require the installation of tracks on the ground, typically I-beam shaped rail tracks. Secondly, they are electric-powered, operating automatically under the drive of electric motors and reducers. Additionally, they are flatbed vehicles with a level surface and no enclosed cabin; in some cases, they can be non-planar but still without a cabin. The vehicles lack a steering wheel, operating only in forward and reverse directions (even turns are made by following the track). These vehicles are characterized by their simple structure, ease of use, high load capacity, resistance to dirt and damage, ease of maintenance, and long service life. Due to their convenience, robustness, affordability, practicality, and ease of cleaning, they have become a transportation tool for frequent short-distance, fixed-point heavy cargo transport within and between factory buildings.

Electric trolleys are mainly used in mobile lifting water carriage applications; in brickworks, kiln factories, refractory plants, ceramic factories, calcining factories, for electric kiln loading and unloading carts, etc.; in engineering, tunnels, and environmental sanitation for electric transport vehicles, electric dump trucks, and electric sanitation collection vehicles, etc. Electric transport and dump trucks are also used in flour mills, ore processing plants, foundries, chemical factories, furnace material factories, and farms, among others.