Professional-C Serums use advanced formulas developed and tested by leading Vitamin C experts. They offer maximum daily antioxidant protection and greater penetration than other Vitamin C products. The greater the penetration, the greater the antioxidant benefit to your skin. Vitamin C can prevent premature signs of aging, including fine lines and wrinkles, protect against future damage, stimulate collagen production for firmer, more resilient skin, and lighten and brighten the skin for a more even tone.