A weekly at-home treatment, not a conditioner, that reduces breakage and visibly strengthens hair, improving its look and feel. Clients can benefit from this global bestseller whether or not they receive chemical services. PRO TIP: Prime your hair for deeper repair with our professional-inspired No.0 Intensive Bond Building Hair Treatment (sold separately). Use No.0 as the first step in a two-part at-home system with No.3 Hair Perfector to strengthen and repair all types of damaged hair. Scientifically Proven: 68% more repair & 3x stronger hair* *When used as a two-part system in just one use. PH Balance: 3.5-5 1 Product in Prestige Haircare* This global best-seller is an at-home treatment, not a conditioner. It reduces breakage and visibly strengthens hair. *NPD Jan 2020-Jun 2021 Repairs damaged and compromised hair Strengthens and protects hair structure Restores healthy appearance and texture Product Tip: Use N 3 before you wash your hair and leave it on for 10 m