Square spigot truss 389*389MM 1)Good stability.lightweight 2)market price 3)6061- ... T6,6082-T6 two types material Square spigot truss 389*389MM truss system:good stability,light weight,6082/T6 materialmain ... shows, outdoor promotion show, etc.Size 220*220mm, 289*289mm,389*389mm,400*400mm,450*450mm,500*500mm,520*760mm,600 ...