Without a doubt, whether the metric is net margin or balance sheet, the most profitable construction companies are full service type, providing“design, engineering, project management, construction and procurement” in the heavy industrial and civil sectors. You can contact Zhejiang Shengyuan Automation Technology Co., Ltd.,Cixi Beilian Electrical Appliance Co., Ltd.,Guangzhou Shenmao Hardware Electrical Appliance Co., Ltd,Chongqing Qiaoxing Machinery & Equipment Company,EC Hardware Co., Ltd. via the red button for more infomation.