This is not a permanenet hair dye, but a hair treatment which gives a color to a hair and nourishes at the same time. The color naturally fades away after 10 washes. You can try a new hair color in every 2 weeks. Unlike a permanent hair dye which expands cuticles to penetrate a color inside, this hair treatment attaches the color pigment on to a surface of the hair. Therefore, there is no cuticle damage. 20 herb extracts nourishes a brittle hair, so even on a seriously damaged hair can have define color and shine.