Thank you for your question. The Home Kit black Haircolor is actually a level 2. It is not a deep deep blue black. It is softer in tone and it will cover gray. For effective gray coverage, apply the haircolor mixture full strength to your new growth liberally. Then take the remaining color mixture and dilute it by half with water to apply to the previously colored hair(Apply full strength to hair that has never been colored). Put on the plastic cap that comes in the kit and let it process at least 35 minutes.