Grasan portable hoppers and bins are available with or without variable-incline belt feed conveyors and variable-rate vibratory pan feeders. Feed hoppers handle materials at rates of 300 to 1,000 tons per hour. Hoppers can be used for a variety of tasks, including loading trucks, barges and rail cars or feeding crushers and screen plants. Typically, bins and hoppers are mounted on a wide flange beam chassis with truck axles, air brakes and signal lights for highway towing. Custom designs are available.