D753 Diesel LocomotivesThe D753 diesel locomotives derive from the reconstruction of a number of locomotives type T478.3 of the Czechoslovak Railways, built between the 1960s and 1970s and nicknamed "Brejlovec" ("Occhialute") because of the characteristic shape of the front windows of the cabs.Starting in 2001, about 40 such machines arrived in Italy, purchased by various private railway companies, after undergoing extensive reconstruction by the Leon D'Oro company to modernize them and adapt them to the safety standards required for the Italian network. Some retained their original diesel engine, classified as D752, while most received a new Caterpillar diesel engine and classified as D753 or DE520 (for those registered by NordCargo).Given their top speed of 100 km/h, they are mainly used for hauling freight trains, both on electrified and non-electrified lines, and have now become a common presence on Italian tracks.