Biokap Nutricolor 7.0 Delicate tints How it works: perfectly covers grey hair, exercising at the same time tempo Nourishing and protective action. Argan oil, with its high content of unsaturated fatty acids and vitamin E, protects, restructures, and adds shine to damaged and brittle hair; willow extract prolongs color hold while protecting hair from UV rays; plant proteins nourish and protect the hair.