These were a surprise on a Sydney bound freighter passing through Coffs Harbour at the end of June. You can't see the wagons due to the bridge girder.
These are Australian Defense Force containers coded ADFU and are a unique size as three across the front equal a 20ft slot, which mean they must be about 2m (or 6ft6) across the front. The length is likely to be the standard container width of 8ft, and they look to be about 8ft6 in height.
As you may be able to see, each small container is locked to the one next to it to make a 20ft unit. As the small containers are individually numbered yet running as a single block, some of the numbers are covered over. The top photo shows 500038, and the bottom photo shows 500045 and 500037.
My kids thought they were pretty cool as they love camo colours. A scale model in this livery would be an interesting additional to a train consist on a model layout.