The CALM buoy provides a single-point mooring for shuttle tankers during offloading operations. Stabilized crude oil is transferred from the Douglas FPSO to the buoy via subsea pipelines and flexible hoses, then onward to the tanker. The buoy is anchored to the seabed by multiple catenary chains and designed to rotate freely, allowing tankers to weather-vane. Facilities include product swivel systems, cargo transfer piping, control and monitoring systems, and emergency release mechanisms. Safety features include remotely operated valves, leak detection, and emergency shutdown interfaces with the FPSO. The installation operates without permanent staffing and is monitored remotely. The Douglas CALM buoy is designed for long-term marine service and reliable tanker export under North Sea environmental conditions.