Commodity inspection. Generally used for import and export trade. Of course, sometimes it is possible to use domestic trade in different places, but less. The commodity inspection agency will issue a certificate to prove the quality and quantity of your goods. The buyer can know whether the quality of the goods is consistent with the demand by the commodity inspection form you issue. Sometimes it will be listed as one of the negotiation documents.China entry exit inspection and quarantine bureau is the most authoritative and largest inspection institution in China. Generally, the export of Chinese products is subject to commodity inspection here. SGS, the most public commodity inspection agency in the world, has offices in major cities in China.