P-66 was designed for ten subsea production wells and eight subsea injector wells. Standardised subsea trees, manifolds, flowlines, risers and umbilicals connect the well system to the vessel. Incoming fluids are separated into oil, gas and water. As the first operating member of the pre-salt replicant series, its oil plant uses a single treatment train comprising a free-water knock-out vessel followed by two electrostatic treaters, providing dehydration and desalting before crude enters the cargo tanks. The gas plant gathers separator and vapour-recovery gas through main compression, molecular-sieve dehydration, Joule–Thomson hydrocarbon-dew-point control and membrane removal of carbon dioxide. Treated gas can then enter export compression, fuel-gas service or reservoir-injection compression; the carbon-dioxide-rich membrane stream is also configured for compression and subsurface reinjection. Integrated water-treatment and water-injection facilities serve the injector network. The standard electrical arrangement uses four gas-turbine generator packages in a three-operating, one-standby configuration, supporting processing, compression, injection, marine and accommodation loads. The 288-metre-long, 54-metre-wide hull contains about 1.6 million barrels of crude storage. Oil is retained in the cargo tanks between lifting operations and transferred to visiting tankers. The gas plant provides pipeline-export and reservoir-injection routes. The vessel’s modular topsides, standardised hull, subsea interfaces and deepwater station-keeping arrangement define the replicant concept applied specifically to P-66.