SST is committed to establishing a supply chain with the goal of sustainable development. In order to ensure the safety of the supply chain working environment, employees are respected and their human rights are protected, business operations promote environmental protection and abide by business ethics, we have formulated a supplier corporate social responsibility commitment , and at the same time carry out supplier sustainability risk assessment and auditing to jointly implement corporate social responsibility and create a sustainable value chain. In addition, in order to lead suppliers to move towards sustainability and fulfill customer responsibility production commitments, a supplier code of conduct and a procurement policy of prohibiting conflict minerals are formulated; suppliers are required to sign a letter of commitment to ensure that suppliers can cooperate with our requirements.