Made of high quality 304 stainless steel, strong and durable,resistance, high hardness, non-toxic and pollution-free. The surface is processed by high-precision mirror polishing,smooth, well Polished without burr, comfortable touch. Heavy Duty 316 stainless steel caps great polished for ultimate corrosion resistant,suit for seaside use. Suitable for boats, yachts, boats and other awning accessories. Rigorous process, each process is strictly in accordance with the technical standards, professional quality inspection layer upon layer check.