A diplomatic bag, also known as a diplomatic pouch, is an envelope, parcel, shipping container or any other kind of receptacle used by diplomatic missions. As long as it is externally marked to show its status, the bag has diplomatic immunity from search or seizure,as codified in article 27 of the 1961 Vienna Convention on Diplomatic Relations. It may only contain articles intended for official use. It need not be a bag. In fact, no size limit is specified by the convention. It is often escorted by a diplomatic courier, who is similarly immune from arrest and detention.