... , chemical plant,petrifaction enterprise.2.Specification: NO. Post dia ball dia handrail dia rai dia tread plate ... ),used in middle and high contruction platform fence post (3)three H=1200(ball middle),used in ... base--tread stair plate5.Advantage: this ball fence post is hot dipped galvanized,anti-rust, cheap and ... , wide usage,easy to maintenance galvanized steel ball-joint post( ISO 9001 factory)