Material: cold rolled steel, anti-corrosion and anti-rust, black baking finish on the surface, environmental protection, not easy to fade, durable Quiet: Ball bearings are fixed inside, low noise and safety: metal stampings have no burrs or sharp edges, Excellent workmanship, sturdy, 360° rotation, smooth movement. Reinforced rivets on the top, solid structure, not easy to loosen, good quality and low price. It is very easy to install and does not require installation. Easy to disassemble for faster daily use. Neat ball bearings make the smoother, perfect for swivel chairs, swivel desks, desks, TVs, bar stools, etc.