WO type iron ore waggon WO 31407 is one of a batch of eleven replacement waggons built by WAGR Midland Workshops between 1970 and 1971 with fleet number 185 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, Binduli Triangle, loaded with fines, 5th June 2010.