Codeage Hair Vitamins delivers a comprehensive hair growth and strength formula with 10,000mcg Biotin alongside Keratin, Collagen, Zinc, Inositol, Silica, and a full spectrum of hair-supporting nutrients — providing every micronutrient and structural building block that hair follicle health and hair shaft integrity require. 120 capsules = 30-day supply.Biotin (10,000mcg) is the primary B vitamin cofactor for keratin synthesis — the structural protein that makes up 95% of each hair strand. Clinical biotin deficiency causes hair thinning and loss, and many people with suboptimal biotin levels see meaningful improvement in hair density and growth rate with supplementation. Hydrolyzed Keratin provides direct structural building blocks for hair shaft formation. Hydrolyzed Collagen provides amino acids (especially glycine, proline, hydroxyproline) for hair matrix and follicle connective tissue. Zinc supports hair follicle cell division and sebum production regulation. Inositol supports insulin signaling that affects hair follicle cycle. Silica supports hair shaft strength and mineral matrix. Non-GMO, gluten-free, dairy-free. Available at Beauty Riche with same-day shipping.