/ˈkʌstəmz ɪnˈfɔːrsmənt zoʊn/ – Phrase
Definition: Khu vực thực thi hải quan.
A more thorough explanation: the area of land and water under the control of the custom’s agency of a particular country
Example: At 24 miles out China and every other coastal nation has a customs enforcement zone that allows it to enforce its customs laws.