Nioxin 3D Intensive Hair Booster is a diameter-protection leave-on treatment, that conditions hair and forms a protective barrier against cuticle damage, and protects thinning hair. This Nioxin Treatment is a leave-on professional hair treatment with KeraPro Complex is particularly designed for progressed-thinning hair and works on specific areas of concern, such as a receding hairline or a low-density crown. Nioxin 3D Intensive Hair Booster with Vitamin Complex gives a warming sensation after application.