A straddle carrier is a non road going vehicle for use in port terminals and intermodal yards used for stacking and moving ISO standard containers. Straddles pick and carry containers while straddling their load and connecting to the top lifting points via a container spreader. These machines have the ability to stack containers up to 4 high. These are capable of relatively low speeds (up to 30 km/h or 18.6 mph) with a laden container. The workers that use this machinery sit at the very top seated facing the middle as they can see behind them and in front of them. Straddle carriers can lift up to 60 t (59 long tons; 66 short tons) which equals up to 2 full containers.