What is the length in mm of an M6 license plate screw?

[ZacharyFitz]

M6 bolts have a diameter of 6mm and a length of 80mm. The function of license plates: A license plate is an identification number for vehicles, serving the same purpose for a car as an ID number does for a person. License plates provide numbering and information registration for vehicles, with their primary function being to identify the vehicle's region of registration through the plate number, and to enable tracking of the vehicle's owner and registration details. Motor vehicle license plate numbers: Motor vehicle license plate numbers consist of a registration authority code and a plate number. For automobile-class plates, the number is structured in two rows - the upper row shows the vehicle registration authority code, while the lower row displays the plate number. The registration authority code consists of 2 characters, combining a Chinese character and an English letter. The Chinese character represents the abbreviation of the province, autonomous region, or municipality directly under the central government, while the English letter indicates the code of the vehicle management office.