... Plated,chromium plated,Tin plated,Black phosphating ,anodized ,Parkerising,and Environmental Plated is used in our products,Hexavalent chromium ... Experience ,good technology1. We are a professional manufacturer with more than 20 years experiences in screw,bolt,nut,washer,rivet ... concept of management.3. We have special research person and more than 100 equipment to produce fastener.Perfect quality 1.In ...