Written requests pursuant to section 516, Tariff Act of 1930, as amended (19 U.S.C. 1516), for information as to the classification, appraised value and rate of duty imposed upon designated imported merchandise shall be submitted in triplicate to the Commissioner of Customs.

The request for information shall contain the following information:

(a) The name of the person making the request, his principal place of business, and the fact that he is a domestic interested party;

(b) A designation of the imported merchandise for which the classification, appraised value and rate is requested; and

(c) A showing of the class or kind of merchandise manufactured, produced, or sold by him which is claimed to be similar to the imported merchandise in such detail as will permit the Commissioner to establish the similarity between the domestic and foreign merchandise.

“Domestic interested party”, when used in this part, means:

(a) A manufacturer, producer, or wholesaler in the United States of a like product,

(b) A certified union or recognized union or group of workers which is representative of an industry engaged in the manufacture, production, or wholesale in the United States of a like product, or

(c) A trade or business association a majority of whose members manufacture, produce, or wholesale a like product in the United States.