It transports natural gas from the Alwyn North, Dunbar, Ellon, Grant, Nuggets, Frigg, Bruce, Ross, Captain, Buzzard, Tartan, Piper, Chanter, Galley, Hamish, Highlander, Ivanhoe, MacCulloch, Petronella, Saltire, and Rob Roy, fields.
[2] The system comprises the Frigg UK pipeline, Alwyn pipeline, other connection lines, and processing facilities at the St Fergus Gas Terminal.
The 110-kilometre (68 mi) long Alwyn pipeline with diameter of 24 inches (610 mm) connects Alwyn North Field with the Frigg Field's TP1 bypass spool.
From the TP1 the 362-kilometre (225 mi) long original Frigg UK Pipeline with diameter of 32 inches (810 mm) runs to the St Fergus Gas Terminal, alongside of the Vesterled pipeline.
[3] An 18-inch (460 mm) diameter pipeline connects Tartan and Piper fields with the Frigg UK Pipeline at the MCP-01 platform, 173 kilometres (107 mi) northeast of Aberdeen.