Metal Screw in precise size ,high qulity and perfect finish on surface. Metal Screw is made by one ... ,powder coating,polishing, threading, sand casting3.different shapes and sizes are workable4.feature:high precision,high quality,reasonable price5 ... sand blasting, polishing, plating, acid treatment, anodizing, painting and PVC powder coating (enamel)6.Inspection: coordinate measuring machine, optical ...