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        Chengde Hengtong Testing Instrument Co. , Ltd. is a  which is engaged in the research and development, production and sales of testing instruments and equipment for polymer materials,  in 2005 after restructuring of state-owned Chengde Testing Machine Co. , Ltd. , it is located in the former Chengde Testing Machine Co. , Ltd. , Shuangqiao, Chengde. The company consists of former Chengde testing machine with many years of product development experience.