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: 4 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. Casting the primary color, the frosted, anti-rust treatment, threaded alignment, chassis formation. Can be made bookshelves, drying racks, put objects, retro lighting, and other crafts. Cast iron is mainly composed of iron, carbon and silicon alloy composition, with high strength, good toughness, plasticity and machinability.