while under fire, many armies with large vehicle fleets also deploy armoured recovery vehicles. These vehicles fulfill a similar role, but are resistant to heavy fire and capable of traversing rough terrain with their tracks, as well as towing vehicles beyond the weight limits of wheeled wreckers, such as tanks (many are based on tank designs for this reason). Each state and territory of Australia has its own regulations and acts for the operation of tow trucks. Tow trucks are generally divided into two categories, either by standard, trade and private towing or accident towing. Accident towing tow trucks are clearly identifiable by number plates ending in either "ATT" or "TT". Tow trucks that are not endorsed for accident towing may use general number plates of any combination pursuant to each state's own registering system. An example of a statute regulating the operation of tow trucks and towing companies in Victoria is the Victorian Accident Towing Services Act. See also Armored recovery vehicle Impounded vehicle auction Motor carrier Roadside assistance Tow hitch Vehicle recovery References External links International Towing and Recovery Hall of Fame and Museum in Chattanooga, Tennessee. Emergency vehicles Tow trucks American inventions