Abstract: A filter cartridge for removing particles or dust from a stream of moving gas or air, including a filter medium disposed between a pleated inner wire support frame, outer longitudinal wire support stays disposed along each inner apex of the pleats of the filter medium, and end caps. The outer wire stays are formed from inwardly bent wires which attach at each end to the inner frame and exert pressure on the filter medium to support it against inner pressure of a pulse jet cleaning device. Preferred filter media are felt or fabric composites containing a layer of porous expanded polytetrafluoroethylene membrane. A preferred form of lower end cap has the periphery contoured to conform to the configuration of the filter medium and inner support frame. The cartridge structure is advantageous in preventing build-up of ledges of dust on protuberances, with consequent reduction of filter efficiency.