FerroChem have developed a ready to use black non fluorescent ink and non fluorescent magnetic ink, FerroChem black for crack detection by MPI. The standard packing is aerosol spray can having 420 ml net content. The suspension medium used is colourless, odourless, low sulphur & chlorine, petroleum based, high flash point oil. The suspension medium does not cause skin irritation thus making the use very user-friendly at sites. The Magnetic Powders used for suspension are highly sensitive to weakest leakage field. FerroChem make, FerroChem Black has found unique application because of the high sensitivity of crack detection at remote and over head applications. The use of white contrast coat to off set unfavorable colour background of the job does not hamper the crack detection sensitivity and has made the use of FerroChem black in combination with white contrast coat very popular.