A. Features 24147 black nickel is nickel-alloy decorative black nickel plating deposits. This deposit can reproduce the surface condition of substrate, and form bright black deposit on the bright substrate surface and a matte black deposit on the non-luster substrate surface. This process can be plating on bright nickel, half-bright nickel, copper and bronze. The deposits is black nickel color which has excellent corrosion resistance, it can be used on the hardware fittings of car, motorbike accessories, spectacle frames, clocks and watched, locks and pens, etc. Cyanide free, good throwing power and covering power. Excellent corrosion resistance and high hardness (700HV) This plating technology may have been declared national patent by Han Lin, please use it correctly.