Red Flag Products Pouralid Water Level System with 1/2-Inch Float Valve (White) 10" Pouralid with detachable color matched plastic lid for pools and ponds 1/2-Inch ABS Auto Fill Valve. The outflow hole is 7-1/4-inches from the top of the unit (Inside Diameter) 3/4-Inch PVC fitting Up to 70 psi of water pressure on the float. Estimated flow rate of 1.5 at 40 PSI 8-1/2-Inches across x 10-1/2-inches tall (Inside Diameter)