What is "fiat-materfer"

The Fiat-Materfer Buenos Aires Underground rolling stock was built by the Argentine company Materfer - then a subsidiary of Fiat Ferroviaria - beginning in 1980 and continuing on through that decade. It was originally conceived to standardise the diverse rolling stock of the Buenos Aires Underground with the use of one model throughout all the lines. However, with the economic and political turmoil faced in the country during and following the collapse of the National Reorganisation Process junta in 1983, its production ended up being far more limited. Today the cars serve as temporary stock for two lines, being phased out as newer models arrive from overseas.