JUST TWIST & COMB. Eliminating greys is as easy as combing your hair. With Just For Men Easy Comb-in Color, one tube of our patented no-mix formula meets one specially designed comb applicator. Just twist & comb it in. Give it 10 mins to blend away the greys, then wash it out, for a natural, grey-free look. Great for targeting grey areas or covering grays throughout your hair. Lasts up to 8 weeks until greys grow back. Can't decide between two shades? Try the lighter one first. You can always go darker later.