WHAT COLOR SHOULD I BUY? BLACK COLOR SELECTION The color with the most problems is black. Some brands tell their customers that if your hair is black, you should use dark brown. This is because the black color keratin powder looks like gray or dark blue on the hair. This is very visible in the sun. Therefore, they are directed to the dark brown color. The black color of the organische hair fiber is matte black. That is, it is the exact color of human hair. You should. *DARK BROWN COLOR SELECTION If you do not see your hair as black when you look in the mirror, you should order a dark brown color product if your hair does not contain even a little dark yellow color. *MEDIUM BROWN COLOR SELECTION If your hair has a dark brown color and there is a dark yellow color in it, you should order a medium brown color. *LIGHT BROWN COLOR SELECTION If you do not have a dark brown color in your hair and it is a single color, like dark blonde, the color you should order is light brown. *YELLOW COLOR SELECTION If your hair is Dark Blonde or Light Blonde, you can order the Yellow Color product.