What is PVD coating ? The PVD is such coating technology that forms a few micron hard films on tools. The hardness of PVD is higher than tungsten carbide super-hard material. In comparison with hard-chromium, intruding too, the PVD film is much harder. The only few microns film is improves...

What is 316L stainless steel ?              The most safe metal for jewelry. 316L Stainless steel refers to weak corrosive of the steel such as air, steam, waterresistance and acid, alkali, salt and other chemical etching, so we called it is acid-proof stainless steel. In...