First, check the appearance quality of the product. For example, the authentic shell material should be strong and not easy to be damaged, and the outer surface of the power supply should be uniform in color, clean and free from scratches and mechanical damage.

The second is to check the mobile phone access sign. According to national regulations, mobile phones can only be sold if they are connected to the Internet. The network access sign is usually posted on the back of the mobile phone and can be seen immediately after the battery is removed. Under the purple light, there will be a bigger sign of "CMII" than the original word. You can also directly enter the network access number (the first line of the network access permission sign), scrambling code (the third line of the network access permission sign), mobile phone body number (dial "* # 06 #") and so on. This website will tell you the authenticity of the mobile phone.

The third is to check the packaging of mobile phones. The package shall include product name, factory name, address, contact telephone number, production date, instructions for use, attachment list, implementation standard code, serial number, network access certificate number, enterprise standard (trademark), model, specification mark and laser anti-counterfeiting mark, as well as corresponding bar codes on the fuselage and package. Mobile phones produced overseas should have the origin of China, the name of the agent, the network access certificate number, the instruction manual, the list of accessories, the warranty certificate, etc.

The fourth is to check the IEMI code of the mobile phone. As long as the GSM digital mobile phone presses "* # 06 #" in turn, the IEMI code of the mobile phone (which can be seen when the battery is removed) is consistent with the IEMI code on the packaging box and the IEMI code on the warranty card.