... is iron , with iron pawod to welding with other iron pole to be a frame;flanch: the thickness is 12mm-20mm ... , the plate with hot-dip galvanized;pole: iron material, inside & outside with hot-dip galvanized, top dimension ... ,uniform luminance sidtribution.Flat glass and optional drop lens changeable. Pole Material:Poles are made by the high-quality metal plants ...