WO type iron ore waggon WO 31401 is leader of a batch of eleven replacement waggons built by WAGR Midland Workshops between 1970 and 1971 with fleet number 180 for Koolyanobbing iron ore operations, with a 75 ton and 1018 ft³ capacity. This unit was converted to WOC for coal in 1986 till 1994 when it was re-classed back to WO. On loaded train 7415 at Binduli Triangle, 29th July 2010.