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743 Perishable Matter with Dry Ice

A mailpiece containing mailable matter that is packed in dry ice (carbon dioxide solid) to cool the perishable contents must meet all requirements in 349 that apply to sending dry ice in domestic mail via air transportation. For air transportation, the amount of dry ice cannot exceed 5 pounds per mailpiece. Dry ice is prohibited to be mailed to international or APO/FPO/DPO addresses.