For best results to achieve 4M (Mahogany Chestnut) on uncolored hair is to apply on 4N (Chestnut). If applied on 1N (Black), 2N (Brown), 3N (Dark Chestnut), the color result will be dark mahogany. If applied on 5N, 6N, 7N, the color result will be light mahogany. The same rules apply for 4D, 4R and 4C. To cover grey hair with 4M, it is essential to mix appropriate quantity of 4N (Chestnut).
See instruction leaflet inside color box or refer to 4N (Chestnut).