the general l shape of the slots 44 and 46 is shown in fig4 as shown in fig2 a bung 52 having a threaded portion 54 and a radial flange portion 56 is threadably engaged with threads 58 on the inside of the inner tubular member 26 the radial flange portion 56 engages the tubular gate member 42 locking the gate member 42 in the closed position as can be seen in fig2 and 3 the bung 52 must be unscrewed and removed in order to move the tubular gate 42 from the fully inserted closed position to the fully withdrawn open position the valve body 14 may be formed in a single plastic molding or formed with the inner tubular member 26 as a separate part as shown in fig2 and 3 in this latter construction the inner tubular member 26 is glued or otherwise bonded to the end portion 22 the apertures 24 and 28 may be aligned radially as shown in fig2 and 3 or may be off set to provide a tortuous path or passage through the valve to limit the rate of tank discharge alternatively the size of apertures 24 and 28 my be varied to regulate the maximum flow rate in the embodiment shown the aperture size.