limit changes, which has resulted in lower average speeds and actual speed limits across the LIRR. Power transmission The LIRR's electrified lines are powered via a third rail at 750 volts DC with the contact shoe running along the top of the rail, similar to on the New York City Subway and PATH systems. This system is incompatible with Metro-North's third rail, which is under-running, though the M8 and M9 fleets are capable of using both types of third rails, as they are equipped with both types of contact shoes. Rolling stock Electric fleet The LIRR's electric fleet consists of 836 M7 and 170 M3 electric multiple unit cars in married pairs, meaning each car needs the other one to operate, with each car containing its own engineer's cab. The trainsets typically range from 6 to 12 cars long. In September 2013, MTA announced that the LIRR would procure new M9 railcars from Kawasaki. A 2014 MTA forecast indicated that the LIRR would need 416 M9 railcars; 180 to replace the outdated M3 railcars and an additional 236 railcars for the additional passengers expected once the East Side Access project is complete. The first M9s entered revenue service on September 11, 2019. Diesel and dual-mode fleets The LIRR also uses 134 C3 bilevel coaches powered by 24 DE30AC diesel-electric locomotives and 20 DM30AC dual-mode locomotives. They are used mostly on non-electrified branches, including the Port Jefferson, Oyster Bay, Montauk, Central, and Greenport Branches. There are also 23 MP15AC locomotives in use as work trains and yard switchers. Named trains For most of its history LIRR has served commuters, but it had many named trains, some with all-first class seating, parlor cars, and full bar service. Few of them lasted past World War II, but some names were revived during the 1950s and 1960s as the railroad expanded its east end parlor car service with luxury coaches and Pullman cars from railroads that were discontinuing their passenger trains. Current Cannonball, a Friday-only 12-car train to Montauk running May through October, with two all-reserved parlor cars with full bar service. Since May 24, 2013, it has originated at Penn Station with a Sunday evening return from Montauk; only the westward train stops at Jamaica. The two rear cars ("Hamptons Reserve Service") have reserved seating and exclusive bar service. The name is a nod to the Cannon Ball, the all-year train to Amagansett/Montauk