The main products of the shangdong science and technology exhibition model ltd. In hoangyang city are hydro-hydrogen models, electrical models of power plants, thermal power models, petrochemical models, building sandpads, electric motor models, large mechanical equipment models, roads and bridges ... Various teaching models, exhibition models, science and technology library models, a large volume model has long been produced for large, middle- and medium-sized enterprises throughout the country and is now being developed into simulation model designs and production and marketing。