... of nuts are made of carbon steel, alloy & stainless steel, aluminum, speaker part top plate/washer 1 ... of nuts are made of carbon steel, alloy & stainless steel, aluminum, brass and other special materials.2 ... Zn,blue/white Zn ,3+ Cr,black Ni,these can change according to customer design 8:For the ... specail requirement ,we can do it according to the drawingMore than 200 modelsSpecifications:1) Made by ...