Abstract: An outlet (10) for unloading a pulverulent lading comprises an outlet body secured to the lower reaches of a railcar in communication with the lading carried by the railcar. The outlet body has an opening therein through which the lading is unloaded. A valve mechanism (30, 32) is movable between a closed and an open position for lading discharge. A valve operator (56, 58) is used to open and close the valves. A sampling port (60) is formed in the valve mechanism. Movement of the valve from its closed position to a sampling position intermediate its closed and open positions, allows a small amount of lading to be discharged only from the sampling port so a sample of the lading may be readily taken. At this time, the valve member blocks the remainder of the outlet so a lading discharge tube (26) cannot be overfilled with lading, and no spillage of lading onto a right of way can occur.