The benefits of '1 unit per carton' are that it’s convenient for retailers at the end point of sale, as they can sell the units directly from the carton. The advantages of '2 units per carton' are that it saves a lot of space during transportation from the factory to the importer and wholesaler, thereby reducing shipping and customs clearance costs. For example, if the shipping cost for a container is 5000 USD and the customs clearance fee per container is 5000 USD, a container can hold 1400 units if packed one per carton, but 2400 units if packed two per carton. The average cost per unit for single packing is 7.143 USD, whereas for double packing, it’s 4.167 USD. From a retail and wholesale perspective, if the labor cost exceeds 3 USD, then single packing should be considered; if the labor cost is below 3 USD, then double packing is more economical. The labor cost mentioned here refers to the expense incurred in repackaging units from '2 units per carton' to '1 unit per carton.'