NEW✨SEALED Chestnut Brown hair can last 3-4 weeks. The hair coloring shampoo only hang on to the surface of the hair shell, It's safer for your hair as well as your skin. (Warm Note): Take a skin test before first using. Must read - CHESTNUT BROWN is NOT designed to cover gray. If you need to 100% cover gray, please be sure to choose black or dark brown. If you receive the wrong color after ordering, please feel free to contact us and we will replace it immediately for you. Our customer service will handle the problem for you within 12 hours. EASY TO USE: Requiring no bowl or brush, just need to put on gloves, and use it the same as normal shampoo, wait for only 8 - 10 minutes(If you want a deeper brown, you can leave the shampoo on for a few more minutes). Doesn't stain your skin. MILD HERBAL FORMULA INGREDIENT: Natural plant formula, Polygonum multiflorum can treat the hair, strengthen the hair roots, make the hair strong and soft. Ginseng extract nourish the hair silk.