A Certificate of Origin (C/O) is required by some countries and is intended to certify to the importing authorities as to which country the products being imported were manufactured in - that is, the C/O certifies that the imported product meets the 'Country of Origin' requirements set by the importing country and which are expected of their foreign suppliers. It may be required that the C/O include information such as local material and labour content. In many cases, a statement of origin printed on company letterhead will suffice, although the document may need to be certified in some way. In other instances, specific types of C/Os may be required, such as the Generalised System of Preferences (GSP) Form A and the Chamber of Commerce C/O.