Amazon Seller Central will ask for the “packing type” of your shipment: Individual products or Case-packed products.
Select Individual products if products in a box have different SKUs or are in different conditions.
Select Case-packed products if products in a box have identical SKUs and conditions and will be sold as individual items. Case packs are not the same as multi-packs: multi-packs are sold as sets, while items in a case pack are sold individually.
For more information see Amazon’s Help Center.