Ultra Easy Comb-In ApplicationNo-mix colour tube, just screw on the comb-in applicator and apply exactly where the grey is. Works for both targeted and all over applications. Ultra Gentle on HairNo ammonia or peroxide. So its gentle on hair. Long Lasting - Natural LookWill not wash out. Lasts up to 8 weeks until the grey grows back. Autostop TechnologyNo-mix formula automatically stops colouring after 10 minutes for perfect colour every time. Just For Men Men's Autostop Hair Colour - A-55 Real Black in Clear