Qingdao Shuangjunli Machinery Manufactory specializes in design, manufacture and installation of temperature control equipment. For years it has committed itself to energy conservation and environment protection and has made a good example in the two aspects. Since its inception, it has initiatively taken part in international communications and cooperation. Its products have reached advanced international level .All the new products were stringently tested and repeatedly experimented to guarantee product quality. The main products contain exhaust fan 50", 30"(other sizes you required), cooling pad and some other temprature controlling equipment, which are used in poultry house, greenhouse, workshop, supermarket, dinning house and some other places that need to be ventilated.