WD-40

WD-40 (Water Displacement, 40th formula) is an American manufacturer and the trademark of a penetrating oil manufactured by the WD-40 Company based in San Diego, California. Its formula was invented for the Rocket Chemical Company in 1953, before it was renamed to the WD-40 Company. It became available as a commercialized product in 1961. It acts as a lubricant, rust preventive, penetrant and moisture displacer. There are specialized products that perform better than WD-40 in many of these uses, but WD-40's flexibility has given it fame as a jack of all trades.

It is a successful product to this day, with steady growth in net income from $27 million in 2008 to $70.2 million in 2021. In 2014, it was inducted into the International Air & Space Hall of Fame at the San Diego Air & Space Museum.