The company effectively plans and controls the entire manufacturing process. Raw materials are strictly purchased from qualified suppliers and quality assurance agreements are signed with them. The incoming raw materials shall strictly follow the incoming inspection system. Unqualified materials shall not be stored. Conduct quality analysis and follow-up investigation on the materials of suppliers every year, and promptly notify them to rectify any problems found. If the same problem occurs three times in a row, the supplier's qualification will be revoked. At the same time, a comprehensive testing method and quality assurance system have been established, and more than 10 million yuan has been invested to establish a physical and chemical testing center. It has the ability to conduct all factory inspections, sampling inspections, most type tests, and raw material inspections. The personnel engaged in inspections have received training from the national testing center and are certified to work. The company has continuously improved and improved its quality system, resulting in a significant improvement in the quality level of its products. The products have all met the standard requirements through national and provincial sampling tests. The production process is strictly controlled by quality, and the operators strictly follow the work instructions and process specifications. A self inspection, mutual inspection, and special inspection system is adopted to ensure that unqualified materials are not used, unqualified semi-finished products are not transferred, and unqualified finished products are not left the factory. If any non conformities are found during the production process, timely organize relevant departments to analyze the reasons and take corrective measures to ensure control effectiveness.