The system comprises two steel wires - a tough one, which carries the weight of the trolley and a lighter one that pulls it. The pulling wire is formed as a continous loop, driven by a 100 kW (140 hp) electric motor. A pair of clamping jaws in the trolley connects to the wire and is held in place with the weight of the trolley itself. The clamp is loosened by rising the upper part of the trolley with the hatches seen just below the pulling wire.

The well lubricated nylon wheels gives a very smooth and silent ride. Here, the barrel is turned upside-down in order to avoid rain uptake.