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You can provide box content information using any one of the methods shown below. If your shipping processes do not support providing box content information, you can choose to skip that step and have Amazon manually process your shipment for a fee.
Enter the information into a web form in Seller Central
Upload an Excel-format or tab-delimited file to Seller Central
Affix a 2D barcode with box content information to each box (this option is available for shipments created in Seller Central and Amazon Marketplace Web Service)
Upload an XML file via Amazon Marketplace Web Service
You must indicate in the shipment creation workflow which method you are using to provide box content information. If you do not indicate one of the methods above, the manual processing fee will be assessed.
Box content information is required even if your box contains a single SKU or single unit. If your entire shipment is packed in a single box, you do not need to provide SKU quantities.
For more information, watch Fulfillment by Amazon: Providing Box Content Information and go to Provide box content information.