Cast iron is mainly composed of iron, carbon and silicon alloy composition, with high strength, good toughness, plasticity and machinability. Casting the primary color, the surface frosted, anti-rust treatment, threaded alignment, chassis formation. Can be made bookshelves, drying racks, put objects, retro lighting, and other crafts. Color: Black Materials: Cast iron Connection Method:screw Size:1/2 inch Inner Diameter:1.8cm Type:axial type Product Usage:floral, lamps, shelves, hanging racks, industrial supplies, and so on Package Included: 6 x flange Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.