The Yellowtail development comprises 51 subsea wells distributed among six drill centres: 26 oil producers and 25 water- or gas-injection wells. Production and injection trees are grouped around subsea manifolds. Flowlines carry oil, gas, produced water and injection fluids between the seabed equipment and FPSO, while risers and electro-hydraulic umbilicals provide fluid transfer, well control, monitoring and chemical services. Onboard processing separates produced water and associated gas from the crude stream. The gas is treated, dehydrated and compressed for FPSO fuel and reservoir reinjection. Produced water is treated onboard, and treated seawater supplies cooling services and reservoir injection. The installation also incorporates crude stabilisation, metering, chemical injection, electrical generation and distribution, flare and pressure relief, firewater, fire-and-gas detection, emergency shutdown, integrated process and subsea controls, cargo handling and accommodation. One Guyana uses a purpose-built "Fast4Ward" multi-purpose-floater hull and standardised topside-module concept. A permanent spread-mooring system connected to seabed anchor piles holds the vessel at a fixed heading without a turret. The ship-shaped hull stores approximately two million barrels of stabilised crude. Oil is periodically transferred to export tankers through the stern tandem-offloading arrangement. The original Yellowtail project has no fixed crude-oil export pipeline to shore; associated gas is managed through onboard fuel use and reservoir reinjection.