Just for men shampoo in colour dark brown black targets only your grey hairs and replaces them with subtle tones that match your own natural hair colour you will see perfect results in just 5 minutes which last up to 6 weeks until the grey hairs grow out just for mens colour shampoo is quickly and easily applied and after it is complete you can shampoo as often as you like and treat your hair the way you always have it is free from ammonia and leaves your hair in great condition once it is