In general, Amazon's self-delivery (Fulfillment by Amazon, FBA) service requires a Standard Product Code (SPC) or an International Trade Item Number (GTIN) for products that need to be sold on the Amazon platform. Among them, the most common product code is the Universal Product Code (UPC).

UPC is a globally unique product identification code that is usually obtained and assigned by product manufacturers to their products. When using the FBA service, Amazon requires you to provide a correct and unique UPC for each product to be sold. This helps ensure product inventory management and tracking on the Amazon platform.

Therefore, if you plan to sell products through the Amazon platform for self-delivery and use the FBA service to provide support in logistics and order processing, you may need to have a valid UPC and provide it to Amazon as a product identification code.