... middle),used in low and many contruction platform fence post (2)higher H=1100(ball middle), ... used in middle and high contruction platform fence post (3)three H=1200(ball middle), ... used in higher contruction platform fence post4.Component column--handrail-rail--bend--capped end ... pipe base--tread stair plate5.Advantage: this ball fence post is hot dipped galvanized,anti-rust, ...