Finmeccanica subsidiary AnsaldoBreda will upgrade 143 light rail coaches for the San Francisco Municipal Railway (MUNI) in the US.
The $54m five-year contract has been awarded by San Francisco Municipal Transportation Agency and the city government.
Work includes revamping the doors, steps, couplers, the ventilation pipes, the wiring and bearings.
Mayor of San Francisco Gavin Newsom said the contract will increase MUNI reliability, increasing the durability of the coaches and convenience for the benefit of passengers.
"By partnering with AnsaldoBreda, we are investing in our tram system to ensure that San Francisco will become one of the most efficient in the world with regard to public transport," Newsom said.