Details: Nioxin Pro Clinical's Summer Duo System 1 is designed for natural, untreated hair with light thinning. Formulated with a powerful blend of niacinamide, biotin and caffeine to help nourish the hair root, stimulate hair follicles and strengthen the hair. Start by applying Scalp + Hair Shampoo to wet hair, gently massaging it into the scalp and hair for one minute before rinsing thoroughly. This gentle cleanser works to remove buildup, including follicle-clogging sebum and environmental residues, preparing the scalp for the next steps. Next, apply the Scalp + Hair Conditioner. Distribute it evenly throughout the hair and scalp, leaving it on for 1-3 minutes. Rinse thoroughly. This conditioner helps to restore moisture balance, while protecting against breakage. For optimal results, use the complete Nioxin System Kit 1 daily.