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Rank the product numbers and service numbers used in the "International Classification" after the names of goods and services, and those that are not included in the "International Classification" The names of commonly used goods and services in my country are also followed by sequence numbers, marked with "C" to distinguish them. Products with a C are unique to China, such as "garlic juice C300124", "monosodium glutamate C300125", "seasoning sauce C30026", etc.