Ardell Lock-in Blonde revives blonde hues, while eliminating unwanted tones during coloring. Its formula facilitates pigment penetration, for a perfect coloring that lasts. It can be used as a gold base filler, as an additive to restore fading blondes and an ash based neutralizer for brassy color. Features Adds shine to hair color Perfects certain tones Sets and locks in hair colors Preserves colors intensity How to use Add 10 drops for every once of hair color. Apply hair color as usual.