* High Potency Vitamin C & Biotin with L-Cysteine & Inositol * Dietary Supplement How It Works: Many factors, including heat, pollution, overwashing, and buildup from styling products can wreak havoc on the condition of our hair. Certain nutrients can help to support against these factors and help to keep hair healthy and strong. Twinlab Hair Factors contains a blend of nutrients including biotin, calcium, and vitamin C that help to keep hair strong and lustrous. Packaged in a glass bottle for maximum stability, quality and freshness.