If a package needs a shipping label, the computer orders one via Bluetooth from a portable printer.

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Poshmark also handles credit card processing and sends the seller a fully filled-out shipping label once a buyer clicks buy.

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At Gazelle.com, we got a box and a shipping label by mail within four days, which made shipping the most convenient.

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When people buy an item from someone on Poshmark, the seller gets a shipping label they print and use to send the item.

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When a product is sold, sellers can print out a shipping label, attach it to the package and drop it at the post office.

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Hardware above the belt scans the "smart" label ubiquitous on the shipping giant's parcels shortly thereafter.

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