Under the import and export trade mode of FOB plus LC, the operation procedures of all parties are as follows: First, after the import and export parties sign the sales contract, the importer should open an irrevocable letter of credit at sight to the exporter as soon as possible. After receiving the letter of credit, the exporter should actively prepare the goods and arrange the export before the latest shipment date stipulated in the letter of credit. If there is an inspection report (commonly known as a passenger inspection certificate) on the documents submitted in the letter of credit, the exporter should contact the guest for inspection after the goods are ready, and ask the guest to issue a passenger inspection certificate after passing the inspection. Then the seller should contact the freight forwarder designated by the guest to book the shipping space. After loading, the shipping company issues the original bill of lading to the seller. The seller shall submit a full set of original documents to his bank before the latest delivery date stipulated in the letter of credit according to the documents required by the letter of credit. After the bank examines the documents, it sends the original documents to the issuing bank of the buyer. If there are no discrepancies in the full set of documents, the buyer's bank shall pay the seller immediately. If there is any discrepancy, the bank will inform the buyer, and if the buyer accepts the discrepancy, he will pay. The seller receives the payment and the whole transaction is over.