Changes the amount of hot and cold water ports/outlets in the Watts dual stem body, model No. P-1079 SKU 452209, when building manifolds with the separate manifold parts or by separating the stem bodies of the P-10PORT or P-20PORT preassembled manifolds and pushing back together. Divider plug slides into the stem end of the dual stem body model No. P-1079 SKU 452209, that you wish to change the hot or cold water distribution. Bagged.