... Most scrows are available.such as :Self tapping threads "A","AB", Threads for chipboard screw,wood screw,drywall screw;Type "M","UNC","UNF","BSW" ... Plated,chromium plated,Tin plated,Black phosphating ,anodized ,Parkerising,and Environmental Plated is used in our products,Hexavalent chromium are ... more than 20 years experiences in screw,bolt,nut,washer,rivet, stud, pin,wrench and so on .2. Our company ...