Hi, good question to ask...
Originaly 1435 mm gauge (used in Ferrocarril Urquiza for long distance passangers rail services or freight trains), locomotive number 7902.
Then was changed to 1676 mm (for been used in Ferocarril Roca for short distance service); now is used in Ferrocarril Mitre with suburban service (Villa Ballester - Zárate) - also 1676 and with numbre A714.
It was repaired and repainted a few months ago.
here you can read more information: http://portaldetrenes.com.ar/ficha/lkd050