Made Iron plating.The carbon steel material features strength,wear resistance and corrosion resistance in environment like high temperature,cold weather,and high humidity areas.Durable and nickel plated surface guarantees protection against environmental damage and rust.Superior rust resistance and oxidation resistance ensures their durability.EASY TO INSTALL:cage nuts and screws accord with standardized metric system.And the average error is less than 0.1mm.The screw thread is quite sharp,clean and accurate without burr.The accurate size makes your installment or repair easier.They fit your cages well,Package includes:meet your different needs.It is a good for both professional and amateur.These multifunctional and nuts are your must-have tools.Widely Applications:Cage nuts and screws are universally compatible with all square-holed racks.nuts and screws are great for mounting your rack server cabinets,server shelves,A/V device enclosures and more. cabinet cage nuts and screwsSize:M6 x 20Fit all square hole racks server rack or cabinetColor:silvermaterial:metalPackage Contents:50* M6 cage nut50* M6*20mm screw