The list below is what I used to make one garden bed. I sourced all my materials except the Corten steel from Bunnings. 1 x 2400mm x 1200mm sheet of 2mm Corten steel cut into 3 x 400mm x 2400mm strips. 1 x 6m length of 10mm straight reo bar. 1 x Galvanised metal flange nut with a 20mm internal thread.