... button 1.materials:sus304,316,brass,aliuminum,steel 2.size:M1-M20 sus304 stainless steel step machine screw Place of Origin ... Guangdongshenzhen China(mainland) Brand Name ZQX Material carbon steel, stainless steel(sus304 sus302 sus316 sus410), copper, aluminum, etc. Size Threads ... will get compensation for that Contact zhengqinxing sus316/sus304 stainless steel safety pin button screw