Possible aircraft debris found on South Australia's Kangaroo Island is not from missing flight MH370.

The object was examined at Australian Transport Safety Bureau laboratories in Canberra and found to be not consistent with the manufacturing specifications of a Boeing commercial aircraft.

The Malaysia Airlines flight, a Boeing 777, disappeared in March 2014 with 239 people on board and is believed to have crashed in the southern Indian Ocean.

Several pieces of debris that authorities say are almost certainly from the plane have been recovered during the past year on the shorelines of South Africa, Mozambique, and Rodrigues and Reunion islands.

American lawyer Blaine Gibson, who previously found debris in Mozambique, has also reported discovering more objects in Madagascar, including personal items such as hand luggage.