She is a Z-28 Patrol Boat. Twenty of then where built by Blohm & Voss to the Argentinean Ministry of the Interior. She has a displacement of about 81 tons, LOA of 28 meters, beam of 5.3 m. and a draft of about 1.7. According to the manufacturer, these boats are capable of a speed of 38 knots are robust and highly manoeuvrable.
One of its sisters, the Islas Malvinas, was captured during the Falklands/Malvinas conflict and was renamed HMS Tiger Bay.
Picture taken at Port of Buenos Aires - Jan. 25th, 2005