REDKEN Bonding Treatment for Damaged Hair Repair Acidic Bonding Concentrate About this item: Redken's most concentrated Bonding Care Complex formula This vegan pre-shampoo rinse-out treatment provides instant results in 5-10 minutes, repairing hair strength inside and out. Apply to wet hair, lather, leave-in 5-10 minutes and rinse. Follow with Acidic Bonding Concentrate shampoo. Strength repair for dry, damaged hair. Using this system results in 2x stronger* and 90% more conditioned* hair. There's no reason to toss your existing haircare just to trying Bonding Care.