Air sampling cane with funnel at one end to avoid water droplets from collecting at edge and being sucked into manifold train. Bulge above the funnel is for glass wool or similar material to allow for filtering of particulates. Codes -22 & -26 feature a #7 Ace-Thred port for introducing calibration gases. See 7508 series watertight roof seal and 7503 series PTFE filter screen.