Serum 10 is an introductory antioxidant serum ideal for all skin types. Formulated with 10% L-Ascorbic Acid USP and no additional key ingredients to ensure a gentle, well-tolerated solution for those with sensitive skin or new to Vitamin C. It is a lightweight, oil-free formula that targets the first signs of aging including fine lines and uneven skin texture and tone. The pharmaceutical grade Vitamin C in this formula, L-Ascorbic Acid USP, is the purest, most potent, and bio-available form of Vitamin C available. Traditionally difficult to stabilize in formulations, this gold-standard ingredient is a cornerstone of Serum 10, made possible by our exclusive IntraDermal System (IDS)®. This proprietary delivery system protects the Vitamin C and enhances penetration into all skin layers, with 2x more Vitamin C retention in the skin overall and 4x more in the dermis, while resisting oxidation to maintain maximum potency and consistent, visible results.