How long is the transit visa issued at Shenzhen airport now?

It is not issued at all, because transit visas upon arrival in China and Shenzhen are not provided. Instead, for transit through airports and ports of China, citizens of Russia and many other countries can obtain a visa-free transit. Visa-free transit is a fundamentally different type of permit, easier to obtain and free of charge. Currently, visa-free transit in China allows you to stay in the country for up to 240 hours (10 days), but with certain conditions. More details about the transfer in Shenzhen are described here - https://nashaplaneta.net/articles1/peresadka-v-aeroportu-shehnchzhehnya

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