Schwarzkopf Professional BC Bonacure Fiber Force Fortifying Primer is a restorative leave-in conditioner spray for very damaged hair. The Fortifying Primer detangles the hair, smoothes it and restores the hair. This spray protects against hair breakage and damage from UV radiation and styling tools. Keratine repairs the damaged hair shaft from the inside out. In addition, this product has been formulated with Panthenol and Bond Connector Technology that form a moisturizing layer around the hair and restore the sulfur bridges in the hair. The result is strong, combable and soft hair that is protected against damage.