400*400mm spigot-type square truss 1.large loading,corrosion resistant 2.Light weight 3.easy to set up 4.15-25 service year ... 400*400mm spigot-type square truss Shape:Can ... : 200*200mm,250*250mm ,300*300mm ,350*350mm ,400*400mm ,289*289mm,389*389mm,400*400mm,450*450mm,500*500mm,520*760mm,600*760 ...