This work presents a joint collaboration effort between Saudi Aramco and Schlumberger for the qualification of a new generation of downhole permanent multiphase flowmeter. We report the validation test of a new permanent completion tool, which is planned to be deployed in horizontal and multilateral wells. The field deployment requires the installation of several stations of the tool for efficient zonal monitoring and control of the reservoir. Each metering station has a miniature flowmeter, water cut sensor, and an electrovalve that can be controlled by the operator to prevent water breakthrough in the production tubing and optimize the oil production. Before the field installation, a unique full-scale two-phase flow loop was built in Saudi Arabia specifically to test the accuracy of the metering devices. A complete physical modeling campaign was designed to model the flow of oil and water in downhole conditions through appropriate matching of defined flow nondimensional numbers. The experimental tests showed excellent results with accurate monitoring of the produced fluids and a smooth control of the oil production.