Good2Gro Biotin Strengthening Serum is a plant derived formulation with Biotin B7, Argan and Rosemary Oil. Builds bonds, repairs all three layers of hair, and reduces the appearance of split ends. Helps nourish your hair follicles, strengthening the roots and promotes thicker and stronger looking hair. Our Serum absorbs quickly into the cortex to strengthen hair from the inside out, improving thinning and hair loss quickly. Restores strength, resiliency, elasticity, volume and adds shine back into the hair. Smoothes and seals the cuticle.