This is Replacement Intex part no. 10184, and is shown in the drawing and parts list as item #12 (4th and 5th pictures). The last picture shows how this part is connected to the pool drain (plunger pushes flap open on inside of pool wall, and threads enable standard garden hose to be connected to the outlet side, which can then direct the drained water wherever desired. I am showing the parts lists from the Round Metal Frame and Easy Set Pools. As far as I can tell, this is the only adapter made Replacement INTEX for their ROUND pools.