Kerastase Resistance Soin Premier Therapiste Pre-Shampoo is the first Reverse Care Conditioner to repair very damaged, over-processed hair. Reverse Fiber Renewal Care Conditioner is created for use before shampoo to protect & repair very damaged, over-processed hair without the weigh-down effect.Kerastase Soin Premier Therapiste acts like a caring gauze to protect the fiber before shampoo. Hair is soft, with a lightweight touch.