65Mn Spring Steel constructed sheel, manganese enhances hardenability and gives a better comprehensive mechanical properties.Carbon Steel constructed nuts with Zinc Plated finish provides great corrosion resistance and antirust ability for a long service life.Square cage nut designed for racks and cabinets with square holes.Mounting your standard rack mountable equipment into a server rack or cabinet.Pre-drill a 14mm x 14mm hole, fits 0.8mm-2.5mm thickness panel.