Fast, inexpensive alternative to black oxide. Imparts a tough, dull black protective finish to ferrous metal parts. Ideal for prototypes, repair parts, and general machine work. The liquid solution is used on small immersible parts. Should be used at room temperature as a cold application. One quart of Tool Black® Solution covers 50 to 75 square feet, however coverage varies with application technique. Tool Black® products cannot be shipped via air transportation.