sentences:  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 after 1988.The main weapon was originally to be two 30-mm guns on a twin-mount, but the reconditioned Bofors were selected to keep costs down; provision was made to install an updated weapon later in the class' service life, but this did not eventuate.