Obagi-C Fx C-Clarifying Serum | 1.0 fl oz Formulated with 4% Arbutin and 10% L-Ascorbic Acid to help minimize the appearance of skin aging for a brighter complexion. The Obagi-C Fx C-Clarifying Serum combines Vitamin C and Arbutin to enhance the appearance of even skin tone for a healthier-looking complexion. Obagi-C Fx System products are ideal for improving the appearance of: Fine lines and wrinkles Dull Complexion Photoaging