Simply Smooth products use the highest quality, purest keratin derived from botanicals and human hair. Using TWO types of quality keratin increases the performance of the treatment. Keratin treatment from human hair goes further into the cuticle than other forms of keratin derived artificially or from animals. Keratin from botanicals have bigger molecules that sit outside the cuticle and gently melt into it. Using these two quality forms of keratin allows the formula to penetrate from inside and out of the hair cuticle, providing better smoothing performance through a natural, healthier process.