This ammonia-free permanent hair colour gel, which uses a very lowpercentage of hydrogen peroxide, effectively covers the grey hair from the first application respecting the hair structure. To achieve 100%grey cover, shades must be mixed with 1n to 8n.a gentle and odourless formula, easy to mix and apply, provides a perfect colour result in only 40 minutes. It can lighten up to 2 tones on virgin hair. The 30 shades of the herbatint line are all perfectly mixable to create your unique colour tone.dermatologically tested on sensitive skin, enriched with 8 organic herbal extracts. Free of ammonia, resorcinol, paraben, alcohol, fragrance and gluten. Suitable for vegans.