The Sunday Riley C.E.O. Rapid Flash Brightening Serum is a product targeted to quickly fight the look of dullness, dark spots, and discolorations at the source, while diminishing the signs of premature aging. It contains 15% advanced Vitamin C, which is a more stable and oil-soluble form of Vitamin C called THD Ascorbate. The serum is highly rated by customers for its brightening effects. Some key ingredients include THD Ascorbate, Phytosterols Complex, and Saccharide Isomerate extract. The product is sulfate-free, paraben-free, gluten-free, phthalate-free, and fragrance-free. The serum is praised for its ability to brighten the skin and boost vital skin bounce, but some users find it expensive and difficult to incorporate into their daily skincare routines. The price of the serum is $85.00 for 1 oz