Keratin Hair Straightening treatments are keratin based, a natural substance that comprises 88% of your hair. During a hair straightening treatment, the keratin penetrates the hair, repairing internal damage, and coats the hair preventing further damage. Thus, leaving your hair looking and feeling healthier than ever. This thermal reconditioning straightening treatment is temporary and completely washes out of your hair in 3-4 months, returning the treated hair back to its natural state.