Boxes without trademarks can be sent by post office. When mailing, it should be wrapped to prevent scratches, and prohibited items should not be put in the suitcase. According to the Directed Catalogue of Prohibited Articles, it is prohibited to post the following articles: firearms include imitations, main parts and ammunition, control devices, explosives, compressed and liquefied gases and their containers, flammable liquids, flammable solids, spontaneous combustion substances, flammable substances in contact with water, oxidants and peroxides, toxic substances, biochemical products, infectious and infectious substances, etc.