Packing Slip

n. receipt that is enclosed with a shipment (usually lists the contents of the shipment, payment information, addressor and addressee, etc.)

A packing slip, sometimes known as a packaging slip or customer receipt, is a shipping document that accompanies delivery packages, usually inside an attached shipping pouch or inside the package itself. It commonly includes an itemized detail of the package contents and may or may not include customer pricing.
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a handling slip that tracks shipping and loading of merchandise.