The Fremantles had a full load displacement of , were long overall, had a beam of , and a maximum draught of . Main propulsion machinery consisted of two MTU series 538 diesel engines, which supplied to the two propeller shafts. Exhaust was not expelled through a funnel, like most ships, but through vents below the waterline. The patrol boat could reach a maximum speed of , and had a maximum range of at . The ship's company consisted of 22 personnel. Each patrol boat was armed with a single 40 mm Bofors gun as main armament, supplemented by two .50 cal Browning machineguns and an 81-mm mortar, although the mortar was removed from all ships sometime in the late 1990s.[citation needed] The main weapon was originally to be two 30-mm guns on a twin-mount, but the reconditioned Bofors were sele