To better implement the Belt and Road Initiative and the Plan for the Coordinated Development of the Beijing-Tianjin-Hebei Region, some ports in the Beijing Municipality, Tianjin Municipality and Hebei Province have launched the 144-hour visa-free transit period, which is targeted at people from 54 countries, following the approval by the State Council of the People's Republic of China. For the details of the countries covered by this preferential policy and the documents needed for visa-free transit, please refer to the link of the special webpage below.
http://english.beijing.gov.cn/travellinginbeijing/144hourvisafreetransit/index.html