Review (5/5): Great colors
It works very well on my black hair. As the instruction indicates, it changed my hair color just in 1 minute. It is easy to grab a thin strip of hair and hold it while combing with the other hand slowly from root to tip several times, then the bright color begin to show up. While combing, a little push on the hair should be necessary but no need too hard. I used the red, blue, and green chalk combs which were so bright under the sunshine. And they are really water based, because the colors were washed easily with water and soap, no mess.