Chapter 4-3 Authority Plates Authority: A. Definition: Authority plates are issued to vehicles that are owned by private industries that serve the public, for example, MBTA, Water Resource Authority. Authority plates can be issued at certain branch offices. B. Plate Types: There are two types of authority plates: Normal Series (Plate Type: ATN) Normal Series plates consist of one to four numbers. Motorcycle Series (Plate Type: AXN) Motorcycle Series plates consist of one to four numbers. ALARS maintains the following Authority Plate codes: Code ATT BAT BRT CAT FRT GMT MBT MBTM MBTP Authority Name Code Greater Attleboro-Taunton Regional Transit Brockton Area Transit Berkshire Regional Transit Authority Name MVRTA Merrimack Valley Regional Transit MRT Montachusett Transit MVTA Martha's Vineyard Transit Authority NRTA Nantucket Regional Transit PVT Pioneer Valley Transit SRT Southeastern Transit TPK Mass. Turnpike Authority WRA Water Resource Authority Cape Ann Transit Franklin Regional Transit Greenfield Montague Transit Mass. Bay Transit Authority Mass. Bay Transit Authority Motorcycle Series Mass. Bay Transit Police WRT Worcester Regional Transit Authority 10/07 4:6