A Single buoy mooring (also known as single-point mooring or SPM) is a loading buoy anchored offshore, that serves as a mooring point and interconnect for tankers loading or offloading gas or liquid products. The parts of a typical SPM includes -

1. Buoy body
2. Mooring and anchoring parts - includes mooring components like Anchors, anchor chains and chain stoppers
3. Product transfer system - hoses etc
4. Other components such as - access to the buoy deck, Fendering to protect the buoy, Lifting and handling equipment to aid materials handling,
Navigational aids for maritime visibility, and fog horn to keep moving vessel alert, An electrical subsystem to enable valve operation and to power navigation aids or other equipment.

Attached the construction of a typical SPM.