A "freight wagon" is, according to ECM Regulation (EU) 445/2011, a non-self-propelled vehicle intended for the transport of freight or other materials used for activities such as construction or infrastructure maintenance activities. The European vehicle number is decisive for the classification of the vehicles. The group of freight wagons includes vehicles whose 12-digit number (known as the standard number) starts with the digits 00 to 09, 10 to 19, 20 to 29, 30 to 39, 40 to 49 or 80 to 89, this number indicating the type of vehicle and its suitability for interoperability.