First Time Buyers: Please send a copy of your ZO Skin Health training certificate to [email protected], your order will only be released once we have this on file. ZO Growth Factor Serum is a lightweight gel for all skin types that strengthens skin, supports skin rejuvenation and protects against future signs of aging. Benefits: Formulated with a combination of plant and enzymatically derived growth factors, clinically proven to: Improve the overall appearance of skin Reduce the appearance of fine lines and wrinkles Improve skin firmness and elasticity Restore hydration and reinforce the skin’s protective barrier