DOT is the English abbreviation of the US Department of Transportation. It was established in 1967 and is headquartered in Washington. It consists of the National Highway Traffic Safety Administration (NHTSA), the Federal Highway Administration (FHWA), and the Federal Aviation Administration (FAA). ), Federal Motor Transportation Safety Administration (FMCSA) and other departments.

DOT certification is a compulsory certification. Among them, the Federal Motor Vehicle Safety Standard (FMVSS) is developed, revised and implemented by the National Highway Traffic Safety Administration of the US Department of Transportation, requiring all motor vehicles and parts and components sold in the United States to pass DOT certification.