All Vitamin C is not created equal. That's why we created this super-concentrated treatment with 10% Tetrahexyldecyl Ascorbate, a super-stable and highly penetratable form of Vitamin C that diminishes the look of dark spots, defends against skin-aging free radical damage, and diffuses discoloration. Cyclopentasiloxane fills fine lines and wrinkles for a visible plumping effect. We formulated our concentrate without water to ensure stability and optimize skin brightening, smoothing, softening and radiance-boosting benefits. Layer under your SPF for an antioxidant boost or apply before you moisturize. It's designed to blend effortlessly into your routine for a noticeable brightening boost.