Series of 7CX-3 trailers manufactured by Shandong Tiansheng machinery CO.,Ltd.meet the national standard. it is mainly used for transportation of farming materials and crops in the field .it consists of two series ,automatic unloading and non-automatic unloading .Automatic unloading consists of side un loading and back unloading ,the qulity is reliable and loading capacity is big .It is easy to be operated and maintained.