WD-40 is a multipurpose lubricant spray that can be used as a rust inhibitor for metal and helps to protect against corrosion. It can also be used as a penetrating oil, helping to loosen stuck or jammed parts. It's ideal for a variety of industrial applications such as maintaining machinery, tools and other equipment, and is also great for cleaning grease, grime and other marks from most surfaces. The list of WD-40 uses is endless!