Duster - A self propelled light tracked vehicle with a  main armament of twin 40 mm cannon mounted in an open-topped turret.  Each gun has a cyclic rate of fire of 120 rounds per minute. It could reach out up to 9,475 meters. Loaded by four round clips, the point detonating, high explosive, tracer rounds would create a dense zone of deadly fragments.  We used them mainly for convoy security.