Discus buoys are round and moored in deep ocean locations, with a diameter of 10–12 metres (33–39 ft).[16][17] The aluminum 3-metre (10 ft) buoy is a very rugged meteorological ocean platform that has long term survivability. The expected service life of the 3-metre (10 ft) platform is in excess of 20 years and properly maintained, these buoys have not been retired due to corrosion.